Mix the dry Ingredients: In a medium mixing bowl, whisk together the gluten-free flour, starch, baking powder, and salt.
1 ¾ cups all purpose gluten-free flour, 1 tablespoon potato starch, ¾ teaspoon gluten-free baking powder, ¼ teaspoon salt
Mix the wet Ingredients: In a large mixing bowl, beat the butter, sugar, milk, vanilla extract, and almond extract until well-mixed and fluffy.
¾ cup butter, ¾ cup granulated sugar, 3 tablespoons milk, 2 teaspoons vanilla extract, ½ teaspoon almond extract
Make and chill the dough: Add the dry ingredients to the wet ingredients and mix until a soft dough forms. Cover and refrigerate for at least 2 hours or up to 2 days.
Roll: Preheat the oven to 350 degrees F and line two large baking sheets with parchment paper or silicone mats. Generously flour the work surface, rolling pin, and your hands with gluten-free flour. Roll the chilled dough about ¼-inch thick.
Cut: Cut into shapes and transfer to the prepared baking sheets, leaving about 1 inch between cookies. Gather and re-roll the scraps, lightly flouring as needed.
Bake: Bake on the middle rack for 11–12 minutes, until the edges are just beginning to turn golden. Cool on the baking sheet for 10 minutes, then transfer to a rack. Cool completely before decorating.