Line a baking sheet with parchment paper and set aside.
In a large bowl, sift flour, salt, and baking soda. Whisk to combine.
In another bowl, add softened butter and white granulated sugar. Beat with a whisk or an electric mixer on low speed for about 10 minutes or until the butter is pale.
Add egg yolk and vanilla extract. Beat again until fully combined.
Add half of the flour mixture to the butter and beat on low speed. Once the batter starts to clump, add the rest of the flour and fold with a spatula to combine.
Place a large piece of parchment paper on your work surface. Turn the dough out onto the paper. Gather the crumbs to form a ball and flatten it out into a disk. Wrap it in cling film and refrigerate for 30 minutes.
Take the dough out, place it in the center of the parchment paper, and place another piece of paper on top of it. This will make it easier to roll the dough out. Using a rolling pin, roll the dough out into a circle, about 1/4” thick.
Remove the upper layer of paper, and cut out your desired cookie shapes using cookie cutters. Transfer the shaped cookies onto the lined baking sheet.
Form the scraps back into a dough and repeat the rolling and cutting process until there is no dough left. This recipe should make 55 cookies (we used 2-inch and 2.5-inch cookie cutters.)
Refrigerate the cookies for at least an hour or until completely firm.
15 minutes before you take the cookies out of the fridge, preheat the oven to 400 degrees Fahrenheit.
Put the cookie tray in the oven, lower the heat to 375 degrees, and bake for 12 minutes or until slightly golden. Allow to cool completely before decorating.