01 -
Whisk together all-purpose flour, baking powder, baking soda, and salt in a medium bowl. Set aside.
02 -
Use a hand or stand mixer to beat the unsalted butter and granulated sugar until light and fluffy, approximately 2 minutes.
03 -
Add the egg, sour cream, and vanilla extract to the creamed mixture and mix until smooth and fully combined.
04 -
Gradually fold the dry ingredient mixture into the wet ingredients, mixing just until incorporated to maintain cookie tenderness.
05 -
Divide dough in half, shape each into a disc, wrap in plastic wrap, and refrigerate for at least 1 hour or overnight for best results.
06 -
Preheat oven to 350°F. Line baking sheets with parchment paper. Roll out chilled dough on a lightly floured surface to ¼-inch thickness and cut shapes using cookie cutters.
07 -
Arrange cutouts on prepared baking sheets and bake for 8 to 10 minutes until edges turn lightly golden. Cool on baking sheets for 2 minutes before transferring to a wire rack to cool completely.
08 -
Beat softened butter until creamy. Gradually add powdered sugar, mixing until smooth. Stir in vanilla extract and 1 to 2 tablespoons milk, adjusting to desired spreadable consistency.
09 -
Optionally divide frosting to tint with food coloring. Spread or pipe frosting onto cooled cookies and garnish with sprinkles if desired. Allow frosting to set before storing.