Homemade Vanilla Cupcakes

and 3/4 cups (200g) cake flour (spoon & leveled)

baking powder

baking soda

salt

unsalted butter, softened to room temperature

granulated sugar

large egg whites, at room temperature

 teaspoons pure vanilla extract

seeds scraped from 1/2 of a vanilla bean

full-fat sour cream at room temperature

(120ml) whole milk at room temperature

vanilla buttercream and sprinkles for decorating