In a medium bowl, whisk the flour, baking powder, baking soda, cornstarch, and salt together.
3 cups all-purpose flour, 1 teaspoon baking powder, ½ teaspoon baking soda, 1 tablespoon cornstarch, ½ teaspoon kosher salt
In the bowl of a stand mixer fitted with the paddle attachment, cream the butter and sugar together. Add in the eggs and mix until combined. Add in the sour cream, and vanilla and almond extracts.
½ cup salted butter, 1½ cups granulated sugar, 2 large eggs, ½ cup sour cream, 1 teaspoon pure vanilla extract, ½ teaspoon almond extract
Mixing on low speed, add in the flour mixture little by little until just combined.
Form the dough into a ball, cover with plastic wrap, and refrigerate for at least 1 hour.
Preheat oven to 350°F.
On a floured surface, roll out the dough to a little more than ¼-inch thick.
Use a 2 to 3-inch round cookie cutter to cut out circles from the dough. Transfer to a baking sheet.
Bake for 7-9 minutes. Transfer the cookies to a baking rack to cool.
While the cookies cool, make the frosting: In the bowl of a stand mixer fitted with the whisk attachment, beat the butter until smooth. Add in the sugar and mix until incorporated. Add in the milk, vanilla and almond extracts, and salt. Add in the drops of food coloring if using, and mix again until fully combined.
½ cup unsalted butter, 2 cups powdered sugar, 1-2 tablespoons milk, ½ teaspoon pure vanilla extract, ¼ teaspoon almond extract, ⅛ teaspoon kosher salt, Food coloring
One the cookies have cooled, frost and top with sprinkles.
2 tablespoons colored sprinkles