Classic White Cake

Preparation

1. Step 1

   Heat oven to 325 degrees. Butter 2 (9-inch) cake pans, and line each with parchment paper. Butter the parchment, then dust with flour, tapping out the excess.

2. Step 2

   To a large bowl or the bowl of a stand mixer fitted with a paddle, add the flour, sugar, baking powder, baking soda and salt, and mix on low to combine. Cut the butter into tablespoon-size pieces and add to the bowl all at once. Mix on low until the butter is evenly distributed and the mixture looks sandy. (A few larger lumps of butter is OK.)

3. Step 3

   Add the milk, oil, egg whites and vanilla extract to a large measuring cup and whisk with a fork to combine. With the mixer on low, slowly stream in the liquid ingredients. When moistened, stop the mixer and scrape the bottom and sides of the bowl to ensure there aren’t any dry pockets. Adjust mixer speed to medium and mix for 1 minute.

4. Step 4

   Divide the batter between the prepared pans, spread evenly and tap the pans on a countertop to release any large air bubbles.

5. Step 5

   Bake the cakes until slightly risen and a toothpick inserted in the center comes out clean, 35 to 45 minutes. The cakes will have a bit of color along the edges, but the tops will still be quite pale.

6. Step 6

   Set the pans on a wire rack and let the cakes cool for about 20 minutes. Then, run a thin knife along the edges of the pan and carefully turn the cakes out onto the rack to cool completely. (You may have to tap the pans gently on the rack to release each cake.)

7. Step 7

   While the cakes bake and cool, clean the mixing bowl and make the buttercream.

8. Step 8

   Assemble the cake: Just before frosting the cake, stir the buttercream vigorously with a flexible spatula to knock out any large air bubbles. (This will help make the final application of the buttercream as smooth as possible.)

9. Step 9

   Add a small spoonful of buttercream to a serving plate or cardboard cake round and place one layer of cake onto the buttercream, dome side up. Spread 1 heaping cup of buttercream evenly over the top of the cake. Place the second layer on top of the buttercream, dome side down, and press gently. Cover the top and sides of the cake with a thin layer of buttercream (be careful not to transfer crumbs back into the bowl of frosting), leaving about 1½ cups buttercream in the bowl. Refrigerate the cake until the buttercream is firm, about 30 minutes.

10. Step 10

    Spread the remaining buttercream over the top and sides of the cake, and decorate with sprinkles. Store the cake at room temperature, loosely covered, for up to 4 days. Use a clean, hot and dry knife for the tidiest slices.