Preheat oven to 350°F. and line a cupcake pan with cupcake liners.
Sift together your cake flour and baking powder.
In an electric mixer, cream together butter and sugar until light and fluffy (about 2 minutes). Add in your vanilla extract and mix well.
Add flour and milk (alternating after each addition). In a small bowl, whisk together egg whites and fold into cupcake batter.
Fill each liner 2/3 full and bake for 17-20 minutes or until toothpick inserted comes out clean. Allow to cool completely before frosting.
Begin with chocolate frosting by creaming ¼ cup butter with cocoa powder in an electric mixer. Alternate ¼ cup heavy cream with 2 ½ to 3 cups powdered sugar until frosting consistency reached. For thicker frosting, add more powdered sugar. For a looser frosting, add more cream (or milk). If piping, you’ll want a thicker frosting.
To make the vanilla and strawberry frosting, beat ¼ cup butter until light and fluffy. Alternate ¼ cup heavy cream with 2 ½ to 3 cups powdered sugar until frosting consistency reached. Separate 2/3 of the frosting and stir in pink food coloring and optional strawberry extract. Stir in the vanilla extract to the remaining 1/3 vanilla frosting.