Preheat oven to 350F degrees. Line (1) muffin tins with 12 cupcake liners. Set aside.
In a medium bowl, mix flour, baking powder, baking soda and salt. Set aside.
In a large bowl, using an electric or stand mixer on medium speed, beat eggs and sugar for about 2 minutes, or until light and creamy. Add the butter and vanilla extract and beat on low speed for about 1 minute, or until well blended. Beat in the dry ingredients on low speed until blended. DO NOT OVER MIX! Add the sour cream and beat until smooth.
Fill each cupcake liner about 3/4 the way full with cupcake batter. Bake 18 to 20 minutes or until toothpick inserted in center comes out clean. Allow cupcakes to cool before frosting.
MAKE THE FROSTING:
Mix softened butter on medium speed with an electric or stand mixer. Beat for 30 seconds until smooth and creamy.
Add powdered sugar, heavy whipping cream and vanilla extract. Increase to high speed and beat for 3 minutes. Add more cream if needed for spreading consistency.
Frost cupcakes using a piping bag or knife. Top with SPRINKLES and enjoy!
Notes
Want to make a cake!? No problem here is this same recipe as a vanilla cake.