- 5 large egg whites
- 1 cup whole milk
- 2 teaspoons pure vanilla extract
- 3 cups all-purpose flour
- 1 ½ cups granulated sugar
- 1 tablespoon plus 1 teaspoon baking powder
- ¾ teaspoon salt
- 12 tablespoons 1 ½ sticks unsalted butter, softened
- Gel food coloring, as desired
- Preheat oven to 350 degrees Fahrenheit. Spray 2 9-inch round cake pans with non-stick cooking spray, line each pan with parchment circles, grease again, and flour. Set aside.
- In a large liquid measuring cup, whisk together egg whites, milk, and vanilla.
- In the bowl of an electric mixer, using the paddle attachment, combine flour, sugar, baking powder, and salt, until well blended. You can also use a whisk to combine the mixture.
- On low speed, add the softened butter, and blend until incorporated. Lumps will form.
- Add liquid ingredients in two stages, stopping the mixer and scraping down the sides of the bowl with a rubber spatula after each addition. Batter should be thick and smooth. Put mixer on medium-high speed for about 5-10 seconds to thoroughly blend all ingredients.
- Measure out approximately 2 ¾ cups of batter into another bowl. Using gel food coloring of your choice, color one or both batters to your liking.
- Using a ¼ cup solid measuring cup for each batter, pour approximately ¼ cup of one color batter in the center of each pan. Do not spread. Using the second clean ¼ measuring cup, pour ¼ cup of the other color of batter directly on top of the first color in both pans. Again, do not spread. Occasionally, swirl the pans or gently hit against the counter to spread the batters. Do not worry if the batters do not reach the outer edges of the pan – batter will spread on its own once all the batter is in the pans.
- Repeat pouring, alternating colors, directly on top of the previous color, until both batters have been used entirely. Batter will come below halfway in each pan.
- Bake for approximately 25-30 minutes, or until a small, sharp knife inserted in the center of each cake comes out clean.
- Remove cakes from pans when barely warm and place on cooling racks or cardboard cake circles. Frost as desired.
Makes 2 9-inch round layers