Preheat oven to 350°F (175°C) and grease three round cake pans.

In a bowl, whisk together flour, cornstarch, baking powder, and sugar; set aside.

In another bowl, cream softened butter and sugar until pale and fluffy. Add eggs one at a time until fully incorporated.

Mix in milk and cotton candy extract until smooth. Gradually add dry ingredients to wet mixture until just combined.

Divide batter into two bowls: color one pink and leave the other white. Pour into prepared pans (one pink layer, two white layers).

Bake for 25-30 minutes or until a toothpick comes out clean. Cool in pans for ten minutes before transferring to wire racks. Frost once cooled.