Instructions

For the Cupcakes

1. Preheat oven to 350 degrees F. Place liners in a standard-sized cupcake tin and set aside. 
2. In a small bowl, whisk together the egg whites with ¼ cup of the buttermilk. Set aside.
3. In a medium bowl, combine cake flour with baking powder and kosher salt. Whisk together and set aside.
4. In a large mixing bowl, beat butter with granulated sugar. Scrape down sides of the bowl as needed and beat for about 2-3 minutes, until fully blended.
5. Beat in vanilla extract.
6. Add in the dry ingredients, slowly, just until combined. Slowly add in the egg mixture, beating until well blended (about 1 minute).
7. Finally, beat in the remaining buttermilk.
8. Spoon batter evenly into the prepared cupcake tin, filling about ½ full. Bake for 17-19 minutes until lightly browned and springs back when you touch it.
9. Remove from oven and cool completely on wire rack.
10. In a small mixing bowl mix together sprinkles, candy stars, and mini-M&M’s.
11. After cupcakes have cooled, cut out the center of the cupcakes and fill with 1- 2 teaspoons of sprinkles candy mixture. Add cupcake top back to the cupcake to hold filling in (it's okay if it doesn't fit perfectly, you'll frost over the top).

For the Frosting

1. For the frosting, beat butter for 3-4 minutes until pale in color.
2. Add powdered sugar, vanilla, and milk. Beat an additional 3-4 minutes until fluffy and smooth!
3. If you want to color your frosting, mix in gel food coloring of choice one drop at a time until desired color. If wanting several colors, separate the vanilla frosting into small bowls and mix in food coloring.