- Makes 12 cupcakes -
2/3 cup (10 tablespoons) unsalted butter at room temperature
1 3/4 cups all-purpose flour
1/4 cup cornstarch
2 teaspoons baking powder
1/2 teaspoon kosher salt
1 1/2 cups sugar
2 large eggs
1 large egg yolk
1 1/2 teaspoons pure vanilla extract
1/4 cup buttermilk or 2/3 cup sour or regular milk
Preheat oven to 350°F.
Sift together the flour, cornstarch, baking powder, and salt.
Using the paddle attachment of an electric mixer, beat the butter with the sugar until light and fluffy, a good 5 minutes.
Add the eggs, one at a time, beating after each, and the egg yolk.
Beat in the vanilla.
Stir in the dry ingredients in thirds, alternating with the buttermilk, just until incorporated. Do not overmix.
Fill lined muffin tins with batter almost to the top. Bake at 350°F for about 20 minutes, or until set.
Vanilla Cream Frosting
1 cup (2 sticks) unsalted butter, at room temperature
1 tablespoon light corn syrup
1 tablespoon pure vanilla extract
pinch of kosher salt
4 cups confectioner's sugar (about 1 pound)
1/4 cup heavy cream
Beat together the butter, corn syrup, vanilla, and salt until smooth.
Blend in the sugar to form a stiff paste.
Slowly beat in just enough of the heavy cream to make a spreadable frosting. If the frosting is too soft, add more sugar or chill it for a few minutes to firm up.