In the bowl of a stand mixer fitted with the paddle attachment, beat the butter and sugar together until light and fluffy, about 3 minutes.
1 cup unsalted butter, ⅔ cup granulated sugar
Add the egg, vanilla, and almond extract and beat at medium speed until well mixed.
1 large egg, 1 teaspoon pure vanilla extract, ¼ teaspoon almond extract
In a separate bowl, whisk together the flour and salt.
2¼ cups all-purpose flour, ¾ teaspoon kosher salt
Add the dry ingredients to the wet ingredients and mix on low speed just until all flour has been incorporated. Do not over-mix the cookie dough or the cookies will be tough.
Scrape around the sides and bottom of the bowl with a rubber spatula to ensure all flour has been incorporated.
Divide the dough into 3 equal portions and place each portion into a separate small bowl.
Color two portions of dough with food coloring and gently mix until the food coloring is incorporated.
Food coloring
Tightly cover each dough with plastic wrap and refrigerate for 30 minutes.
While the dough chills, preheat oven to 350°F. Line 2 baking sheets with parchment paper. Set aside. Pour sanding sugar into a small bowl (if using).
Coarse sanding sugar
Remove the chilled cookie dough from the refrigerator.
Begin forming the cookies by scooping about 1 teaspoon of each of the three colors of dough per cookie. Roll the colored dough together to form a cookie dough ball. Roll the ball of tie dyed dough into the sanding sugar. Place onto prepared baking sheet and slightly press the dough down - just until the top is flattened a little. Repeat, placing cookies 2 inches apart on the baking sheet, until all dough is used.
Bake for 8-10 minutes, or until edges are just set.
Let cookies cool for 1 minute on the baking sheet, then transfer to a cooling rack to completely cool.