Preheat the oven to 350℉ (177℃). Line a cupcake pan with 12 cupcake liners.
In a small mixing bowl, whisk together the all-purpose flour, baking powder, and salt. Set aside.
In the bowl of a stand mixer fitted with a paddle attachment or in a large mixing bowl with an electric hand mixer, cream the granulated sugar, unsalted butter, and vegetable oil until light and creamy. Add the egg whites, sour cream, and vanilla and almond extract and mix until smooth.
Add half of the flour mixture to the wet ingredients and mix on low speed until mostly combined. While mixing on low, slowly pour in the milk and mix until combined. Add the remaining flour and mix on low speed until well combined and smooth. Fold in the rainbow sprinkles.
Portion the cupcake batter into the cupcake liners about 3/4 full. Bake the cupcakes for 20 minutes until the cupcakes bounce back when gently touched. Cool the cupcakes in the pan for 5 minutes and then transfer the cupcakes to a wire rack to cool completely.