01 - Preheat 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. Set aside.
03 - In a large mixing bowl, beat the softened unsalted butter, granulated sugar, and light brown sugar using an electric mixer on medium speed until pale, light, and fluffy, approximately 3 minutes.
04 - Add the eggs one at a time, mixing well after each addition. Blend in the pure vanilla extract and cotton candy flavoring until the mixture is smooth and homogeneous.
05 - Gradually add the dry ingredient mixture to the wet ingredients on low speed, mixing until a soft, cohesive dough forms. Do not overmix.
06 - Divide the dough evenly into two separate bowls. Add a few drops of pink gel food coloring to one portion and blue gel food coloring to the other. Fold and mix each until the color is uniform throughout.
07 - Pinch off a small amount of dough from each colored portion and gently roll them together in the palms of your hands to form a 1.5-inch ball with a swirled marbled effect. Arrange on the prepared baking sheets, spacing each ball about 2 inches apart.
08 - Bake in the preheated oven for 9 to 11 minutes, or until the edges are set and the centers remain soft. Avoid overbaking to maintain a chewy texture.
09 - Allow the cookies to rest on the baking sheets for 5 minutes, then carefully transfer to a wire cooling rack to cool completely.
10 - If desired, top each cooled cookie with a small tuft of cotton candy just before serving for a whimsical, festive presentation. Note that cotton candy dissolves quickly, so add it at the last moment.