– 1/2 cup unsalted butter – 1 cup granulated sugar – 3 egg whites, room temperature – 1 1/2 tsp vanilla extract – 2 tsp baking powder – 1/2 tsp salt – 1 1/2 cups cake flour – 1/2 cup milk, room temperature – Red food coloring – Blue food coloring
– 3 cups confectioner's sugar – 1 cup butter, softened – 1 tsp vanilla extract – 2-4 tbsp milk, as needed
Preheat the oven to 350° Line a muffin tin with 12 cupcake liners. Beat the softened butter until smooth and creamy. Add in the granulated sugar and beat until smooth. Add the egg whites and the vanilla extract. Mix until frothy. In a separate bowl, sift together the cake flour, baking powder, and salt. Slowly add the dry ingredients into the wet ingredients. Alternate the dry ingredients with the milk. Beat until the ingredients are incorporated.
1Divide the batter into 3 separate cups of batter. Add red food coloring to one cup of batter, blue batter to the second cup of batter, and leave the third cup of batter uncolored. Equally divide the red batter into the 12 cupcake liners, approx. 1 tablespoon into each liner. Repeat the process with the white batter and top off with the same process for the blue batter.
Bake in the preheated oven for 14-16 minutes. Once the center of the cupcakes come out clean by sticking a toothpick into the center of them, they are done and ready to be removed from the oven to cool. Allow the cupcakes to cool completely before frosting.
Beat the unsalted butter until the butter is smooth and creamy. Mix in the vanilla extract and add the confectioner's sugar one cup at a time. Beat in the milk one tablespoon at a time until the desired consistency is reached for spreading or piping. Decorate with sprinkles if desired.