Preheat Oven:
Preheat your oven to 350°F (175°C) and prepare a baking sheet by lining it with parchment paper.
Mix Dry Ingredients:
In a medium bowl, whisk together the flour, baking powder, and salt. Set aside.
Cream Butter and Sugar:
In a large mixing bowl, blend the softened butter and sugar together until creamy and light. Add the egg and cotton candy flavoring, mixing well until fully incorporated.
Combine Ingredients:
Slowly add the dry ingredients to the butter mixture, mixing until just combined. The dough may be a little crumbly.
Color the Dough:
Turn the dough out onto a surface lightly sprinkled with powdered sugar or flour. Divide the dough into two equal portions. Add pink food coloring to one portion and blue food coloring to the other, working each portion until the color is evenly distributed.
Roll and Layer the Dough:
Roll out each portion of colored dough to about ¼ inch thickness. Place one sheet of dough on top of the other, gently patting to remove any air pockets. Roll the layered dough tightly from one side to the other, like a jelly roll.
Slice and Bake:
Slice the rolled dough into ¼ inch thick slices and place the cookies on the prepared baking sheet. Bake for 7-9 minutes, being careful not to let the cookies brown. Allow the cookies to cool on the baking sheet for at least 20 minutes before transferring them to a cooling rack.
Prepare the Icing:
Remove the lid and aluminum seal from the container of icing and microwave for 1 minute. If desired, stir in 1 teaspoon of cotton candy extract for extra flavor.
Decorate the Cookies:
Add the icing to a piping bag and pipe it over the cookies, or use a spoon to drizzle the icing over the tops. While the icing is still wet, add sprinkles if desired.
Let the Icing Set:
Allow the icing to dry completely before stacking the cookies. If stacking, place parchment or waxed paper between each layer to prevent sticking.