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Black+Decker Convection (CTO6335S) vs Mueller 4 Slice Toaster Oven Side-by-Side Comparison

Alan Nguyen
Reviewer
Nguyen Ntk
Visual Specialist
Updated
Tested Using Methodology v1.0
Updated Apr 3, 2023
Tested Using Methodology v1.0
Updated Apr 3, 2023
The front of a closed stainless steel Black+Decker CTO6335S Countertop Convection Toaster Oven on a white background.
The front of a closed stainless steel Mueller MT-175 4-Slice Countertop Toaster Oven on a white background.

Our Verdict

6.7
Overall Score
  • Performance (50%)
    7.0/10
  • Design (25%)
    6.6/10
  • Usability (25%)
    6.1/10
6.1
Overall Score
  • Performance (50%)
    7.0/10
  • Design (25%)
    5.3/10
  • Usability (25%)
    5.2/10

The Black+Decker Convection Toaster Oven (CTO6335S) and the Mueller 4 Slice Toaster Oven (MT-175) have some interesting strengths and weaknesses of their own. As our best budget toaster oven and our best-value small pick, their overall scores don’t differ too much from one another.

Design-wise, the Mueller is simply an analog toaster oven with 3 control knobs. Meanwhile, the Black+Decker has an LCD and 13 control buttons for more precise adjustments of timer and temperature.

The Mueller has a neat detachable crumb tray which makes it easy to clean, especially for a small toaster oven. On the other hand, the Black+Decker has a large cooking chamber to minimize grease splashing to the walls. Both ovens don’t have an interior light though.

The most interesting aspect between these two toaster ovens is that their performance scores are equal. Upon a closer look, the Black+Decker has the added benefits of having a convection system and more heating elements, resulting in higher scores in roasting whole chicken and baking fries. In contrast, the Mueller has just the right balance of capacity and power to score higher in toasting bread and baking pizza, both of which don’t require convection.

BLACK+DECKER CTO6335S Countertop Convection Toaster Oven Performance

Mueller 4-Slice Toaster Oven Performance: Good Heat Distribution
7.0
Performance Scores
  • Toast (40%)7.0/10
  • Pizza (25%)6.8/10
  • Whole Roasted Chicken (25%)7.7/10
  • Baked French Fries (10%)5.6/10
7.0
Performance Scores
  • Toast (40%)7.5/10
  • Pizza (25%)7.6/10
  • Whole Roasted Chicken (25%)7.0/10
  • Baked French Fries (10%)3.6/10
7.0

Toast

7.5
From left to right, 24 pieces of toast for the top and bottom of three toast levels including lighter, medium, and darker.
On the left: Level 3; In the middle: Level 4; On the right: Level 5
From left to right, 24 pieces of toast for the top and bottom of three toast levels including lighter, medium, and darker.
The top and bottom of the best four pieces of toast from the stainless steel Black+Decker CTO6335S Convection Toaster Oven.
On the left are the top and bottom of four pieces of toast from the first batch, and on the right are from the second batch.
Taste: 7.5
50% * 7.5 = 3.8
Even Surface Color: 7
20% * 7 = 1.4
Consecutive Usability: 6
30% * 6 = 1.8
  • Function: Toast
  • Number Of Slices: 4
  • Toast Level: 4/7
  • Cooking Time: 5m 10s
  • Second Batch: 3m
  • Convection: No

With our Toast test, we were able to determine that level 4—5 minutes 10 seconds on the timer—was the best option scoring a 7/10. Levels 3 and 5 respectively had a lighter and darker than ideal, although even, surface color.

The toast level 4 of the Black+Decker scored a 7/10 for color. The four pieces had areas of different colors ranging from golden brown to just slightly golden. This was probably due to uneven heating of the elements and the convection fan not running.

Despite the color, the first batch was crispy on the outside and soft on the inside so we gave it a 7.5/10 for taste. Our head chef Tuyet Pham determined that it would go great with eggs benedict and omelet.

Even with the automatic toast time adjustment feature, the quality of the second batch was reduced in every aspect. The color was lighter and the texture was less crispy so we had to give it a 6/10 for consecutive usability. If you want the second batch to be the same as the first, lower the toast level by one.

Mueller 4 Slice Toaster Oven Toast Test
From left to right, 24 pieces of toast for the top and bottom of three toast levels including lighter, medium, and darker.
The top and bottom of the best four pieces of toast from the stainless steel Mueller MT-175 4-Slice Countertop Toaster Oven.
On the left are the top and bottom of four pieces of toast from the first batch, and on the right are from the second batch.
Taste: 8
50% * 8 = 4.0
Even Surface Color: 7
20% * 7 = 1.4
Consecutive Usability: 7
30% * 7 = 2.1
  • Function: Toast
  • Number Of Slices: 4
  • Toast Level: ⅓ to Dark
  • Cooking Time: 4m
  • Second Batch: 4m
  • Convection: No

For our Toast test, we started off by trying the Medium Toast setting which was around 3 minutes 5 seconds on the timer. The four pieces of bread on the upper tray level came out only lightly toasted on top except for one golden brown piece. We then cranked it up to the Dark Toast setting—around 4 minutes 50 seconds on the timer—which, unfortunately, burnt the toast a bit.

Finally, we opted for the middle ground which was 4 minutes on the timer—⅓ of the rotation from Medium to Dark. This setting was tricky to get right on the time dial, so we used an external timer. It gave us the best possible toast results from this oven scoring a 7.5/10 in total.

After 4 minutes of toasting, the four pieces of toast had pretty good surface color. However, the colors varied from light golden to golden brown on both the top and the bottom, so we could only give a 7/10.

Luckily, the varied colors partially meant varied textures which were all good and deserving an 8/10. The golden brown areas had a more crispy outside while the light golden areas had a softer inside. Our head chef Tuyet Pham determined that it would go great with omelets, eggs benedict, and sandwiches but not so much with soup.

After taking out the first batch, we immediately put four more pieces inside to test the oven’s consecutive usability which ended up at 7/10. Also under the identical toasting time, the four pieces of bread became brown with an increased evenness from the first batch. While the color was a bit darker than ideal, the extra crispiness made the second batch more suitable for soups.

6.8

Pizza

7.6
A toaster oven baked 9-inch thick-crust meat pizza with cheese, onions, and green bell peppers on top inside a baking pan.
A toaster oven baked 9-inch thick-crust meat pizza with cheese, onions, and green bell peppers on top inside a baking pan.
Two slices of oven baked 9-inch thick-crust meat pizza with cheese, onions, and green bell peppers on top of one another.
Two hands break apart a slice of pizza with melty cheese, meat, and green bell peppers on top baked using a toaster oven.
Cooking Time: 7.5
20% * 7.5 = 1.5
Crust: 7
20% * 7 = 1.4
Toppings: 6.5
30% * 6.5 = 1.9
Taste: 6.5
30% * 6.5 = 1.9
  • Function: Bake
  • Temperature: 450°F
  • Cooking Time: 7m 30s
  • Convection: Yes

The Black+Decker did an ok job of baking a 9-inch thick-crust meat pizza earning it a 6.8/10.

Compared to the recommended 10 minutes on the label, it took 7m 30s to bake the pizza, which was fairly solid. However, after comparing it to other toaster ovens in our Pizza test, we could only give it a 7.5/10.

The crust had a good golden brown color but was soft and a little dry — possibly due to the longer cooking time. Thus, it could only get a 7/10.

The toppings were mostly dry with an uneven coloring, plus the cheese wasn’t melty so it got a 6.5/10.

In the end, our chef gave the pizza a 6.5/10 for taste.

Mueller 4 Slice Toaster Oven Pizza Test
 Mueller 4 Slice Toaster Oven PizzaA toaster oven baked 9-inch thick-crust meat pizza with cheese, onions, and green bell peppers on top inside a baking pan.
Two slices of oven baked 9-inch thick-crust meat pizza with cheese, onions, and green bell peppers on top of one another.
Two hands break apart a slice of pizza with cheese, meat, onions, and green bell peppers on top baked using a toaster oven.
Cooking Time: 6
20% * 6 = 1.2
Crust: 8
20% * 8 = 1.6
Toppings: 8
30% * 8 = 2.4
Taste: 8
30% * 8 = 2.4
  • Function: Toast
  • Temperature: 450°F
  • Cooking Time: 9m
  • Convection: No

For its low power draw, the Mueller did pretty well in our Pizza test with a score of 7.6/10.

The oven took 9 minutes to bake a 9-inch thick-crust meat pizza which was slightly faster than the label’s recommended 10 minutes. However, compared to our tested toaster ovens, it could only be a 6/10.

The crust had a golden color all the way through and the inside was still moist. If only the crust was a bit more crispy, it would’ve gotten higher than an 8/10.

The toppings were also caramelized quite evenly from the meat and veggies to the cheese, worthy of another 8/10. The cheese was nicely melted but the areas closer to the back of the cooking chamber were more caramelized compared to the rest.

With both the crust and the toppings being 8/10, our chef had no reason to give the pizza one final 8/10 for taste.

7.7

Whole Roasted Chicken

7.0
A whole roasted chicken using a toaster oven on a silver broiling rack and baking pan on a white background.
A whole roasted chicken using a toaster oven on a silver broiling rack and baking pan on a white background.
A tray of whole toaster oven roasted chicken. The thermometer has two probes inside the chicken and displays 189°F and 192°F.
Seven pieces of a carved chicken including a carcass, two breasts, two wings, and two thighs on a silver baking pan.
Two hands pulling apart a roasted chicken thigh. In the white background is the rest of the roasted chicken on a baking pan.
Cooking Time: 8
20% * 8 = 1.6
Skin: 6.5
20% * 6.5 = 1.3
Doneness: 8.8
20% * 8.8 = 1.8
Taste: 7.5
40% * 7.5 = 3.0
  • Function: Bake
  • Temperature: 350°F
  • Cooking Time: 1h
  • Convection: Yes

Following our Whole Roasted Chicken test guidelines, we placed a 3 lb chicken on a broiling rack on a baking pan of the Black+Decker with plenty of space to spare. The abundance of space gave it some advantages over smaller units like the Breville BOV450XL despite a lower power output. Overall, the Black+Decker received a 7.7/10 for this test.

It took the oven 1 hour, the standard amount of time, to roast the chicken to a desirable color so we gave it an 8/10. The skin came out a light golden color but it was uneven despite being flipped after the first 40 minutes. In addition, it was soft, so it got a 6.5/10.

The chicken was thoroughly cooked but the internal temperature was a tad bit high at 189°F-192°F compared to the USDA recommended 165°F-180°F so we gave it an 8.8/10. The meat was very juicy but the lack of roasted aroma and crispy skin resulted in a 7.5/10 for taste from our chef.

Mueller 4 Slice Toaster Oven Whole Roasted Chicken Test
A whole roasted chicken using the Mueller MT-175 Toaster Oven backside up on a silver baking pan on a white background.
A whole roasted chicken using the Mueller MT-175 Toaster Oven belly up on a silver baking pan on a white background.
A tray of whole toaster oven roasted chicken. The thermometer has two probes inside the chicken and displays 185°F and 192°F.
Eight pieces of a carved chicken including two carcass halves, two breasts, two wings, and two thighs on a baking pan.
Two hands pulling apart a roasted chicken thigh. In the white background is the rest of the roasted chicken on a baking pan.
Cooking Time: 6
20% * 6 = 1.2
Skin: 5.5
20% * 5.5 = 1.1
Doneness: 8.7
20% * 8.7 = 1.7
Taste: 7.5
40% * 7.5 = 3.0
  • Function: Toast
  • Temperature: 350°F
  • Cooking Time: 1h 20m
  • Convection: No

The Mueller could barely fit a 3 lb chicken for our Whole Roasted Chicken test. Nonetheless, the result was quite decent at 7/10 in total. If you were to purchase this oven and use it to roast a whole chicken, we recommend cutting it open or chopping it into pieces beforehand.

We first placed the chicken backside down on the baking pan. When we slid the pan in, the top of the chicken breast grazed the upper heating element’s guard and was seared.

After the first 40 minutes, we flipped the chicken to find out that parts of the skin on the back got stuck to the baking pan. Then, when we reinsert the pan, the same problem with the breast happened to the back. Luckily, they weren’t burnt.

However, even after 1 hour and 20 minutes, most of the chicken skin still hasn’t reached a desirable color. The chicken, for the most part, looked like it was steamed and not roasted, so we gave the skin a 5.5/10.

Nonetheless, our chef decided to stop the roasting as the color wouldn’t improve anyway and to avoid overcooking the meat. This cooking time was the equivalent of a 6/10 according to our data.

With such a long cooking time, the meat had no pink spots. However, the chicken’s internal temperature was 185°F-192°F, higher than the USDA recommended 165°F-180°F. Thus, we gave it an 8.7/ for doneness.

While not the most appetizing looking, the meat was very juicy. That, combined with the slight caramelization on the skin, was enough for a 7.5/10 for taste from our chef.

5.6

Baked French Fries

3.6
Pieces of baked french fries using a toaster oven on a silver baking pan on a white background.
Pieces of baked french fries using a toaster oven on a silver baking pan on a white background.
A close-up of pieces of baked french fries using a toaster oven on a silver baking pan.
Six pieces of broken-up baked french fries are stacked on top of pieces of whole fries on a silver baking pan.
Cooking Time: 0
20% * 0 = 0.0
Color: 7
20% * 7 = 1.4
Texture: 6.8
20% * 6.8 = 1.4
Taste: 7
40% * 7 = 2.8
  • Function: Bake
  • Temperature: 400°F.
  • Cooking Time: 25m 50s
  • Convection: Yes

With a score of 5.6/10, the Black+Decker left a lot to be desired in the Baked French Fries test. In comparison, the same-sized Cosori CO130-AO did a much better job with its higher power output and air fry basket.

This oven took 25m 50s to bake 12 oz of fries which was just a bit too long over the limit of our Baked French Fries test. Thus, it failed our cooking time section. Coloring was uneven among the fries ranging from nicely golden to almost none so they could only get a 7/10.

The textures were also uneven and, worse, none was particularly good. The golden fries were only a little crispy and the ones that lacked color were soft. Overall, it was a 6.8/10 for this test.

Our chef gave the resulting fries a 7/10 for taste.

Mueller 4 Slice Toaster Oven Baked French Fries Test
Mueller 4 Slice Toaster Oven Baked French FriesPieces of baked french fries using the Mueller MT-175 Toaster Oven on a grooved silver baking pan on a white background.
A close-up of pieces of baked french fries using the Mueller MT-175 Toaster Oven on a baking pan on a white background.
Ten pieces of broken-up baked french fries are stacked on top of pieces of whole fries on a grooved silver baking pan.
Cooking Time: 0
20% * 0 = 0.0
Color: 4.5
20% * 4.5 = 0.9
Texture: 4.5
20% * 4.5 = 0.9
Taste: 4.5
40% * 4.5 = 1.8
  • Function: Toast
  • Temperature: 400°F
  • Cooking Time: 27 m
  • Convection: No

Our Baked French Fries test brought out the Mueller’s weakness of not being able to maintain a high temperature due to its low power draw. Its even heat distribution couldn’t help much if the temperature wasn’t high enough, so the final score was 3.6/10.

We stopped the baking after 27 minutes as the fries weren’t getting any more colors. This, nonetheless, was over our time limit of 25 minutes, so it was a 0/10.

The fries had no significant color change and barely enough for a 4.5/10. We ended up with 12 oz of frozen fries that were more similar to being dried in an oven than being baked, so we gave them another 4.5/10 for texture.

Fortunately, the fries were cooked through and not soggy, so our chef could give them a 4.5/10 for taste and not a zero.

Sturdy but Lacking

Black and Decker CTO6335S Design Review

Stainless Steel Mueller 4-Slice Toaster Oven Design Review: Standard
6.6
design Scores
  • Exterior (20%)5.0/10
  • Interior (30%)7.0/10
  • Build Quality (50%)7.0/10
5.3
design Scores
  • Exterior (20%)5.0/10
  • Interior (30%)1.0/10
  • Build Quality (50%)8.0/10

In the Black and Decker CTO6335S Convection Toaster Oven Box

In the Mueller MT-175 Small Toaster Oven Box
An oven rack, a user manual, the BLACK+DECKER CTO6335S Convection Toaster Oven, a box, a baking pan, and a broiling rack.
  • Model: CTO6335S
  • Warranty: 2-year limited (not applicable in Latin America)
  • User Manual
  • Baking Rack
  • Baking Pan
  • Broiling Rack

The packaging has some eye-catching illustrations and information as well as was able to keep the oven and its three accessories in place. However, there are only two foam pads on the sides to cushion the oven while the accessories are positioned with duct tape.

A box, the Mueller MT-175 4-Slice Toaster Oven, a recipe booklet, a baking pan, an oven rack, a user manual, and a brochure.
  • Model: MT-175
  • Warranty: 1 year
  • User Manual
  • Baking Rack
  • Baking Pan

The Mueller toaster oven came in a basic packaging and positioned with two foam pads. The included accessories were simply duct-taped to the oven. Inside the box are also a user manual and a simple recipe booklet.

5.0

Exterior

5.0
A closed front of the Black+Decker CTO6335S Convection Toaster Oven with exterior measurements on a white background.
A closed front of the Black+Decker CTO6335S Convection Toaster Oven with exterior measurements on a white background.
The front of a closed Black+Decker CTO6335S Convection Toaster Oven has a control panel and the right has ventilation holes.
The back and left sides of the Black+Decker CTO6335S Toaster Oven. The back has air ventilation holes and two black buffers.
  • Weight:
    12.9 lbs (5.8 kg)
  • Length:
    19.3" (49.0 cm)
  • Width:
    13.4" (34.0 cm)
  • Height:
    10.6" (27.0 cm)
  • Material:
    Stainless steel
  • Color:
    Silver
  • Door Handle:
    cool-touch
  • Tray Indicators:
    No
  • Crumb Tray:
    Slide-out

Despite its large size, the Black+Decker only has air ventilation holes around the side where the convection fan is. The two buffers on the back to keep the oven from being too close to the walls are quite sturdy. Also, a slide-out crumb tray is always a nice touch.

Our measurements of the oven’s footprint were 19.29" x 13.38" x 10.62" which were a lot different in terms of length and height compared to the manufacturer’s 22.8" x 13.4" x 15.5".

A closed front of the stainless steel Mueller MT-175 4-Slice Toaster Oven with exterior measurements on a white background.
A closed front of the stainless steel Mueller MT-175 4-Slice Toaster Oven with exterior measurements on a white background.
Mueller 4 Slice Toaster Oven ExteriorThe front of a closed stainless steel Mueller MT-175 4-Slice Toaster Oven has a control panel and the right has holes.
The back and left sides of the Instant Omni Plus 18L have air ventilation holes. The back has a power cord and two buffers.
The top, front, and right sides of the Black+Decker TO1760SS 4-Slice Natural Convection Toaster Oven on a white background.
On a white background, the bottom of the Mueller MT-175 Toaster Oven has a detachable crumb tray, four stands, and holes.
The detached crumb tray of the stainless steel Black+Decker TO1760SS 4-Slice Countertop Toaster Oven on a white background.
  • Weight:
    9.0 lbs (4.1 kg)
  • Length:
    15.0" (38.0 cm)
  • Width:
    11.6" (29.5 cm)
  • Height:
    8.9" (22.5 cm)
  • Material:
    Stainless steel
  • Color:
    Gray
  • Door Handle:
    Cool-touch
  • Tray Indicators:
    No
  • Crumb Tray:
    Detachable

As simple as it is, the Mueller has all the standard exterior features of a small toaster oven but also something more. The bottom of the oven acts as a detachable crumb tray which not only makes it easy to remove the falling bits and crumbs but also to clean the entire interior.

The oven has a cool-touch door handle and back buffers to prevent it from being too close to the wall. Unfortunately, it has no cord storage or carrying handles.

Our measurements of the oven’s footprint were 14.96" x 11.61" x 8.86" which pretty much coincided with the manufacturer’s 14.84" x 11.85" x 8.86". However, the weight of the oven by itself was already 9 lbs whereas the label said the entire box was 7.63 lbs.

Control Panel

Control Panel of the Small Mueller MT-175
The BLACK+DECKER CTO6335S Toaster Oven’s control panel has an LCD and 13 buttons for 8 cooking functions and 5 features.
  • Type:
    LCD display + 13 buttons
  • Temperature:
    200°F - 450°F
  • Timer:
    1 minute - 2 hours
  • Indicator Light:
    Yes
  • Status Bar:
    No
  • Light Toggle:
    No
  • Convection Toggle:
    Yes
  • Rotation Toggle:
    No
  • Automatic Preheat:
    Yes
  • Audio Cues:
    No

The control panel consists of an LCD digital display, two buttons to adjust time and temperature, a timer toggle, a convection toggle, eight buttons for functions, and a start/stop button.

The control panel of the Black+Decker TO1760SS 4-Slice Toaster Oven has 3 control knobs for temperature, function, and timer.
  • Type:
    3 control knobs
  • Temperature:
    150°F - 450°F
  • Timer:
    1 minute - 30 minutes + stay-on
  • Indicator Light:
    Yes
  • Status Bar:
    No
  • Light Toggle:
    No
  • Convection Toggle:
    No
  • Rotation Toggle:
    No
  • Automatic Preheat:
    No
  • Audio Cues:
    No

The Mueller has a basic analog control panel with three dials for temperature, function, and time. The time dial has a stay-on setting to help with its short range, similar to many other small toaster ovens. Interestingly, while the max temperature setting was 450°F, we actually recorded the internal temperature of the oven reaching 500°F on the said setting.

Cooking Functions of the Black and Decker CTO6335S Digital Convection Toaster Oven

Cooking Functions
The BLACK+DECKER CTO6335S’s cooking functions include Cookies, Pizza, Frozen snacks, Potato, Bake, Broil, Toast, and Bagel.
  • Cookies
  • Pizza
  • Frozen snacks
  • Potato
  • Bake
  • Broil
  • Toast
  • Bagel

The eight cooking functions are useful for beginners and experienced cooks can freely adjust the time and temperature of each to their liking.

The function dial of the Black+Decker TO1760SS 4-Slice Toaster Oven has 3 cooking functions including Bake, Broil, and Toast.
  • Toast
  • Bake
  • Broil
  • Keep warm

Different from most other toaster ovens, the Mueller’s Bake function only uses the lower heating elements as opposed to lower and upper. The Broil function still uses only the upper heating elements.

The Toast function is where both the lower and upper heating elements work. Nonetheless, the oven still provides all the basic functions for its intended purposes.

7.0

Interior

1.0
The BLACK+DECKER CTO6335S’s cooking chamber has 4 quartz heating elements with guards, 2 levels, and a convection fan cavity.
The BLACK+DECKER CTO6335S’s cooking chamber has 4 quartz heating elements with guards, 2 levels, and a convection fan cavity.
The stainless steel BLACK+DECKER CTO6335S Convection Toaster Oven’s cooking chamber has a convection fan cavity on the right.
  • Heating Elements:
    4 quartz
  • Convection Fan:
    Yes
  • Lighting:
    No
  • Tray Levels:
    2
  • Rotisserie:
    No
  • Safety Hook:
    No

The Black+Decker only has two tray levels but you can make use of the flippable rack to effectively create two more levels. The oven has a convection system but no internal lighting—unlike the Ninja DT201—which can be an inconvenience considering the interior is black.

The oven has quartz heating elements that use infrared light to cook. They have their own safety guards to prevent direct contact with baking pans and trays.

Compared to the more common nichrome heating elements, they produce more heat and cool down faster. They are also more energy-efficient and easier to clean but don’t last as long in terms of durability. However, if grease splashes onto the heating elements while cooking, it’ll leave permanent stains.

Mueller 4 Slice Toaster Oven InteriorThe Mueller MT-175 4-Slice Toaster Oven’s cooking chamber has 2 quartz heating elements with guards and 2 guide rails.
Mueller 4 Slice Toaster Oven InteriorThe Mueller MT-175 4-Slice Toaster Oven’s cooking chamber has 2 quartz heating elements with guards and 2 guide rails.
The Mueller MT-175 Oven has 1 bottom heating element with a guard and 2 guide rails on its right cooking chamber wall.
  • Heating Elements:
    2 quartz
  • Convection Fan:
    No
  • Lighting:
    No
  • Tray Levels:
    2
  • Rotisserie:
    No
  • Safety Hook:
    No

Similar to many other small toaster ovens, including the Comfee CFO-BB101, the Mueller lacks a convection fan and an interior light. In addition, it only has two heating elements which can usually lead to uneven heat distribution compared to four or more heating elements.

These heating elements are made of quartz which uses infrared light to cook foods faster than the more common nichrome counterparts. Quartz heating elements also cool down faster, are more energy-efficient and easier to clean but not as durable.

However, if grease splashes onto the heating elements while cooking, it’ll leave permanent stains. This is why they usually have guards which this oven also has.

Capacity

Capacity of the Mueller 4-Slice Toaster Oven
An opened front of the BLACK+DECKER CTO6335S Convection Toaster Oven with interior measurements on a white background.
  • Length:
    14.2" (36.0 cm)
  • Width:
    12.6" (32.0 cm)
  • Height:
    7.9" (20.0 cm)

The CTO6335S can comfortably fit 6 slices of toast, a 12-inch pizza, and a 3 lb whole chicken. While the manufacturer didn’t state the oven’s capacity, we measured the cooking chamber’s volume to be around 23 liters.

An opened front of the stainless steel Mueller MT-175 4-Slice Toaster Oven with interior measurements on a white background.
  • Length:
    10.6" (27.0 cm)
  • Width:
    9.8" (25.0 cm)
  • Height:
    7.5" (19.0 cm)

We could fit four slices of toast, a 9-inch pizza but we could barely fit a 3 lb chicken inside the Mueller, unlike the same-sized Breville BOV450XL. We measured the cooking chamber volume to be around 12.81 liters, slightly different than the manufacturer’s provided capacity of 11.67 liters. However, it could just be a difference in measuring standards.

Power Cord the Black And Deck Convection Toaster Oven

Power Cord
A three-pronged plug power cord. In the background is the stainless steel BLACK+DECKER CTO6335S Convection Toaster Oven.
  • Length:
    24.8" (63.0 cm)
  • Type:
    3-prong plug
  • Power:
    1500 W
  • Rated Output:
    120 V ~ 60 Hz

Even though the length of 24.8" is enough for household use, the power cord protrudes from the bottom of the oven reducing the usable length. In addition, it’s not long enough to wrap around the two back buffers.

A two-pronged plug power cord. In the background is the stainless steel Mueller MT-175 4-Slice Countertop Toaster Oven.
  • Length:
    30.7" (78.0 cm)
  • Type:
    2-prong plug
  • Power:
    1100 W
  • Rated Output:
    120 V ~ 60 Hz

The power cord is 30.7 inches long, suitable for household use. Unfortunately, the oven doesn’t have any storage space for it.

Baking Rack

Accessories

Baking Rack
A stainless steel baking rack of the stainless steel BLACK+DECKER CTO6335S Convection Toaster Oven on a grey background.
  • Length:
    14.2" (36.0 cm)
  • Width:
    10.0" (25.4 cm)
  • Height:
    0.9" (2.2 cm)
  • Material:
    Stainless steel
  • Dishwasher Safe:
    Yes

The baking rack can be placed in the oven either way up, effectively adding two more tray levels for the oven.

A stainless steel baking rack of the Mueller MT-175 4-Slice Countertop Toaster Oven on a white background.
  • Length:
    10.5" (26.7 cm)
  • Width:
    8.8" (22.4 cm)
  • Height:
    0.5" (1.3 cm)
  • Material:
    Stainless steel
  • Dishwasher Safe:
    Yes

The two sides of the baking rack have slight curves upward at an angle to keep the baking pan in place. It fits perfectly with the guide to help prevent accidents when placing your food in the oven.

Baking Pan

Accessories

Baking Pan
A silver baking pan of the stainless steel BLACK+DECKER CTO6335S Convection Toaster Oven on a grey background.
  • Length:
    13.3" (33.8 cm)
  • Width:
    10.2" (25.8 cm)
  • Height:
    1.2" (3.0 cm)
  • Material:
    Stainless steel
  • Dishwasher Safe:
    Yes

The baking pan is large and, being 100% compatible with the broiling rack, it catches all the drippings. This prevents any hot mess from dirtying the heating elements thus mitigating that potential fire hazard. However, it’s not 100% non-stick so you may have some stubborn stains to deal with after a heavy roasting session.

A grooved silver baking pan of the stainless steel Mueller MT-175 4-Slice Countertop Toaster Oven on a white background.
  • Length:
    10.2" (25.8 cm)
  • Width:
    7.9" (20.0 cm)
  • Height:
    0.6" (1.5 cm)
  • Material:
    Stainless steel
  • Dishwasher Safe:
    Yes

The baking pan doesn’t fit into the guide rails and has to on top of the rack. This may prevent the full use of the oven’s capacity and lead to some inconveniences during cooking.

On the bright side, the pan has ridges and grooves to give your food attractive roasting marks and catch the dripping better. It has a coating but is not completely non-stick so you may need to watch out for some stubborn stains after a hefty roast.

Broiling Rack

Accessories

A silver baking rack of the stainless steel BLACK+DECKER CTO6335S Convection Toaster Oven on a grey background.
  • Length:
    11.7" (29.7 cm)
  • Width:
    8.7" (22.0 cm)
  • Height:
    0.7" (1.9 cm)
  • Material:
    Stainless steel
  • Dishwasher Safe:
    Not advisable

The broiling rack is designed to fit the baking pan perfectly while the holes are there to help with air circulation around the food. It doesn’t have a coating though so it may be prone to stains, caramelized bits of food, and discoloration.

7.0

Build Quality

8.0
The front of an opened BLACK+DECKER CTO6335S Convection Toaster Oven with a baking rack, a baking pan, and a broiling rack

The Black+Decker CTO6335S is equipped with a tamper-resistant screw to prevent removal of the outer cover. However, the bottom tray can easily slide out and the door can also open if you tilt the oven.

Throughout our tests, we noticed that the oven’s large capacity is somewhat counteracted by its power output of 1500 W. We speculated on its ability to perform more efficiently if it were 1800 W.

The front of an opened stainless steel Mueller MT-175 4-Slice Countertop Toaster Oven with an oven rack and baking pan.

For a simple small toaster oven, build quality is all about how durable it is and if it works properly. The Mueller accomplishes that with a sturdy stainless steel casing and smooth-turning dials.

Much to Be Desired

Black+Decker Countertop Convection Toaster Oven Usability

Muller 4-Slice Toaster Oven Usability: Easy but Not Convenient to Use
6.1
usability Scores
  • User Control (30%)8.0/10
  • Ease of Use (50%)5.0/10
  • Cleanability (20%)6.0/10
5.2
usability Scores
  • User Control (30%)6.0/10
  • Ease of Use (50%)4.0/10
  • Cleanability (20%)7.0/10
8.0

User Control

6.0

The Black+Decker has 8 functions but the convection toggle is only applicable to Bake. There’s an indicator light for when a function starts and stops — which are two separate buttons on the control panel.

For all functions except Toast and Bagel, you can push the increment and decrement buttons once to change the temperature in increments of 5°F and hold to change in increments of 25°F. After pressing the Timer button, the same goes for cooking time but in increments of 1 minute and 10 minutes. For Toast and Bagel, simply choose a level from 1 to 7.

Unfortunately, even though the label shows a stay-on function, we couldn’t find it in the control panel or the user manual. A small thing we didn’t like about the buttons was that they sometimes didn’t respond well.

Even though the Mueller only has three simple control dials, there are a few things to keep in mind. For the timer knob, when setting it to less than 10 minutes, always rotate past 10 minutes and then rotate back to the desired time.

It’s always tricky to precisely adjust time and temperature for an analog-control toaster oven and this one is no different. Nonetheless, you can use an external timer and an oven thermometer to get more accurate readings.

If you frequently use the stay-on feature, you can turn off the oven by rotating the function dial to Off instead of the timer.

5.0

Ease of Use

4.0

For all functions except for Toast and Bagel, the Black+Decker has an automatic preheat feature. This will always heat the heating elements to 350°F, which takes around 4m 20s, before starting the actual timer. Then, the internal temperature will gradually stabilize around your input temperature.

One thing to note is that you cannot change the temperature or time during the automatic preheat cycle. You can only do so once the oven reaches the selected temperature.

Keep in mind that the oven’s exterior gets hot to the touch quite quickly. In addition, it doesn’t turn off upon opening the door, unlike some others. The door also can’t be opened partially.

This oven beeps with each push of a button and does so three times when it finishes cooking. The oven always remembers the last selected setting until it’s unplugged. It’s advised to unplug the oven after you finish using it as the digital display doesn’t turn off after a period of no interaction.

What’s convenient about 100% analog toaster ovens is that it’s very simple to adjust time and temperature during cooking. When the timer runs out, a bell will sound and the oven will shut off. Afterward, you can freely leave it plugged in and not worry about power consumption as it has no digital display.

The door can open at any angle < 50° to let food cool down inside the oven. However, keep in mind that opening the door doesn’t stop the oven. The exterior shell isn’t very thick, so it gets hot to the touch quite quickly during cooking.

6.0

Cleanability

7.0
Grease on the broiling rack of the stainless steel BLACK+DECKER CTO6335S Convection Toaster Oven.
Grease on the broiling rack of the stainless steel BLACK+DECKER CTO6335S Convection Toaster Oven.
Grease on the baking pan of the stainless steel BLACK+DECKER CTO6335S Convection Toaster Oven.
The cleaned broiling rack and baking pan of the stainless steel BLACK+DECKER CTO6335S Convection Toaster Oven.

We cleaned the Black+Decker following our toaster oven cleaning guide. With the oven having an internal and external coating, cleaning was quite straightforward.

However, even with the slide-out crumb tray, we still had to tilt the oven to get all of the crumbs out. In addition, some of them got stuck inside the heating element safeguards and we had no way of getting them out.

Mueller 4 Slice Toaster Oven CleanabilityPermanent stains on the left cooking chamber’s ceiling and the upper heating element’s guard of the Mueller MT-175 Oven.
Mueller 4 Slice Toaster Oven CleanabilityPermanent stains on the left cooking chamber’s ceiling and the upper heating element’s guard of the Mueller MT-175 Oven.
Permanent stains on the right cooking chamber’s ceiling and the upper heating element’s guard of the Mueller MT-175 Oven.
The cleaned grooved silver baking pan of the stainless steel Mueller MT-175 4-Slice Countertop Toaster Oven.

We clean the stainless steel exterior with no problem. However, after the chicken test, there were burnt bits stuck to the upper heating element’s guard and grease on the cooking chamber’s ceiling. There was ample space between the ceiling and the upper heating element, so we proceed to try every cleaning method possible.

Unfortunately, we could only scrub off the bits. Due to the interior not having a non-stick coating, there were some permanent stains on the cooking chamber’s ceiling and the upper heating element’s guard.

Luckily, the heating element itself was intact. Also, we were able to remove the stubborn stains on the baking pan by brushing them with a paste of baking soda and water.