01 - Preheat oven to 350°F. Line two baking sheets with parchment paper and set aside.
02 - In a medium bowl, whisk together the flour, baking powder, baking soda, and salt until evenly combined.
03 - In a large bowl, beat the softened butter, granulated sugar, and brown sugar using an electric mixer until light and fluffy, about 2-3 minutes.
04 - Beat in the egg, vanilla extract, and cotton candy flavoring until the mixture is smooth and well combined.
05 - Gradually add the dry ingredients to the wet mixture, mixing on low speed until just combined. Do not overmix.
06 - Divide the dough evenly into two bowls. Add pink gel food coloring to one bowl and blue to the other, folding gently until soft pastel shades are achieved.
07 - Pinch off a small piece of dough from each colored batch and gently press them together to form a swirled ball. Place on the prepared baking sheet, spacing each ball about 2 inches apart. Optionally, roll each dough ball in sprinkles before placing on the sheet.
08 - Bake for 9-11 minutes, until the edges are just set and the centers still look slightly underbaked. Remove from the oven.
09 - Let the cookies rest on the baking sheet for 5 minutes, then transfer to a wire cooling rack to cool completely before serving or storing.