01 - Preheat the oven to 350°F. Line two baking sheets with parchment paper and set aside.
02 - In a medium bowl, whisk together the all-purpose flour, baking powder, baking soda, and salt until evenly distributed.
03 - In a large bowl using an electric or stand mixer, beat the softened butter, granulated sugar, and packed brown sugar on medium speed until the mixture is light and fluffy, about 2 to 3 minutes.
04 - Beat in the egg, vanilla extract, and cotton candy flavoring until fully incorporated and smooth.
05 - Gradually add the dry ingredient mixture to the wet ingredients, mixing on low speed until just combined. Avoid overmixing.
06 - Divide the dough evenly into two separate bowls. Add pink gel food coloring to one portion and blue gel food coloring to the other, folding gently until soft pastel shades are achieved.
07 - Pinch off a small piece of dough from each colored portion and gently press them together to form a swirled, multi-colored ball. Place on the prepared baking sheets spaced about 2 inches apart. Optionally, roll each ball in colored sprinkles before placing on the sheet.
08 - Bake for 9 to 11 minutes, until the edges are just set and the centers still appear slightly underbaked. Remove from the oven.
09 - Allow the cookies to rest on the baking sheets for 5 minutes, then transfer to a wire cooling rack to cool completely before serving or storing.