Blue-Ribbon Vanilla Cake

Step 1 -Arrange a rack in the center of the oven.

Step 2 -Preheat the oven to 350 degrees F.

Step 3 -Lightly coat two 9-inch cake pans with nonstick cooking spray.

Step 4 -Line the bottoms of the pans with parchment paper rounds.

Step 5 -Lightly coat the paper rounds with nonstick spray.

Step 6 -Whisk the flour, the cornstarch, the baking powder, 2 teaspoons of the salt, and the baking soda in a large bowl until combined. Set the mixture aside.

Step 7 -Beat 2 sticks of the butter, the granulated sugar, the vegetable oil, and 1 tablespoon of the vanilla with an electric mixer on medium-high speed until light and fluffy, about 3-4 minutes.

Step 8 -Add the eggs and the egg yolks, one at a time, to the batter and beat to blend between each addition. Occasionally scrape down the sides and the bottom of the bowl, until the batter is completely combined, smooth, and creamy.

Step 9 -With the mixer on low speed, add the dry ingredients mixture in three additions, alternating with the buttermilk, whisking between each addition. Begin and end with the dry ingredients.

Step 10 -Evenly scrape the batter into the prepared pans and smooth the tops of the cakes.

Step 11 -Bake the cakes, rotating the pans halfway through cooking, until the cakes are light golden-brown and a tester inserted into the center comes out clean, about 35-45 minutes.

Step 12 -Transfer the pans to a wire rack and let the cakes cool for 30 minutes.

Step 13 -Run a knife around the edges of the cakes and invert them onto a wire rack to cool completely.

Step 14 -Beat the remaining butter in a medium bowl with an electric mixer on high speed until smooth, about 1 minute.

Step 15 -Reduce the speed to low and gradually mix the confectioners' sugar into the butter until completely smooth.

Step 16 -While mixing, add the heavy cream, the remaining vanilla, and the remaining salt into the frosting mixture.

Step 17 -Increase the speed to high and beat until the frosting is light and fluffy, about 2 minutes.

Step 18 -Place one of the cakes, domed-side down, on a platter.

Step 19 -Evenly spread about 1 1/2 cups of the frosting over the top of the cake.

Step 20 -Place the remaining cake, domed-side up, on top of the frosted cake.

Step 21 -Spread the top of the cake with 1 1/2 cups of the frosting.

Step 22 -Frost the sides of the cake with 1 1/2 cups of the frosting. Don't worry if parts of the cake peak through, as this is just a base layer.

Step 23 -Refrigerate until the frosting is set, about 30 minutes.

Step 24 -Spread the remaining frosting over the top and sides of the cake and smooth it out.

Step 25 -Slice and serve.