Source: Cook's Illustrated via Can You Stay for Dinner?
1 and 1/2 cups flour
3/4 cup white sugar
2 teaspoons baking powder
1/2 teaspoon salt
1 stick butter (room temperature)
1/2 cup sour cream
2 large eggs (room temperature)
2 teaspoons vanilla extract
Preheat the oven to 350 degrees, and line a cupcake tin with 12 paper cupcake liners.
Sift together flour, sugar, baking powder, and salt into the bowl of an electric stand mixer.
Add butter, sour cream, eggs, and vanilla. Beat everything at medium speed for about 30 seconds until the batter becomes smooth and satiny.
Scrape down the sides of the bowl with a spatula and mix by hand until all ingredients are incorporated and the batter is smooth. The batter will be slightly thick.
Fill cupcake liners about 3/4 full and bake about 20 - 22 minutes, until cupcakes are golden.
Cool cupcakes completely on a wire rack before icing.