Preheat the oven to 350°F. Line 2 muffin pans with cupcake liners.

In a bowl, combine the flour, sugar, baking powder, and salt. Add the cold butter and mix until crumbly.

In a separate bowl, mix half of the milk with vanilla. In another bowl, whisk egg whites and remaining milk.

Gradually add the milk mixture to the flour mixture, beating on medium-low speed for 5 minutes. Stir in the sprinkles.

Fill cupcake liners 2/3 full and bake for 17-20 minutes until set. Cool before frosting.