Yellow cake and chocolate frosting are meant for each other. This recipe combines a moist made from scratch yellow cake with creamy chocolate frosting. Stays fresh for days and is the perfect family birthday cake!
Ingredients
4egg whites = ½ cup whites
1cupunsalted room temperature butter
1 ¾cupgranulated sugar
4large egg yolks PLUS 2 whole eggs, total of 2/3 cup of egg
4tablespoonscanola or vegetable oil, I do not recommend coconut oil in this recipe
1teaspoonvanilla
1cuproom temperature buttermilk or substitute, see recipe notes
2 ½cupscake flour
1teaspoonbaking powder
½teaspoonbaking soda
½teaspoonsalt
Chocolate Buttercream Frosting:
1cupunsalted butter, slightly softened
½cupunsweetened cocoa powder
1teaspoonvanilla
6cupspowdered sugar
dash of salt
cream, milk or half and half to thin the frosting (about 2-3 tablespoons)
Instructions
*This recipe requires 6 eggs total, separated
Place the rack in the middle of the oven and preheat the oven to 350 degrees while preparing the cake. I let my oven preheat for a full 15-30 minutes before baking.
Grease and line two 9-inch round cake pans, three 8-inch pans or one 9x13 pan on bottom and sides. I also line the bottoms of the round pans with parchment paper to ensure the cake does not stick.
In a clean bowl of stand mixer fitted with wire whisk attachment, whip ½ cup of room-temperature egg whites at high speed until stiff peaks form. This usually takes about 1 minute or less. Scrape beaten egg whites into a clean bowl and set aside.
After removing the egg whites from mixing bowl, (no need to clean out bowl) mix butter with paddle attachment for a few seconds in the bowl. With the mixer on medium high, gradually add 1 ¾ cups sugar until mixed well. Scrape down the sides of the bowl.
Add 4 egg yolks plus 2 eggs (⅔ cup total egg) to the sugar and butter mixture. Mix for a few seconds, scrape down sides to ensure all ingredients are incorporated.
Add oil and vanilla to the mixture on medium speed. Scrape down the sides of the bowl again.
Add the buttermilk and all of the dry ingredients (cake four, baking powder, baking soda and salt) to the bowl. Mix on low until dry ingredients are no longer visible. Then mix on medium high for about 5 seconds. Turn off the mixer. Do not over mix! Remove the bowl from the stand mixer and place the bowl on the countertop.
Using a large spatula, gently fold the egg whites into the mixture in the bowl until the streaks of whipped egg whites no longer are visible. This takes a few seconds by hand. Pour the batter into prepared pans.
Bake until cake layers begin to pull away from the sides of pans and the toothpick inserted into the center comes out clean, 25-28 minutes.*
Cool cakes in pans on a wire rack for 20-30 minutes.
Chocolate Buttercream Frosting:
Place one cup of room temperature butter into bowl of a stand mixer or large bowl. Turn on mixer and blend until butter is smooth, about 20 seconds.
Add the unsweetened cocoa powder and vanilla to the butter and mix on low until smooth.
Add 3 cups of the powdered sugar to the bowl and mix on low, add pinch of salt.
Add remaining 3 cups of powdered sugar, a half cup at a time, alternate with cream or milk to thin the frosting. Scrape down sides occasionally. When all ingredients are incorporated, Beat frosting on medium high speed for 2-3 minutes until smooth.
Assembing the Cake
Place one layer of the cake on a platter or cake stand. Place a dab of the frosting on the middle of the plate before placing the cake layer on to help it stay in place.
Frost with about 1/3 of the frosting. Place the other layer on top. Frost the sides and then the top. Cake is ready to eat immediately, or will stay fresh for two days.
Cover the cake loosely with saran wrap or use a cake dome to store the cake. The cake does not need to be refrigerated.
Notes
Since egg sizes vary so much, and the amount of eggs in a cake are key ingredients, I measure the eggs after cracking for best results. See notes on recipe regarding eggs.
Make sure the eggs, butter and buttermilk are at room temperature.
If your eggs are cold, place in a bowl of warm water for a few minutes until at room temperature.
Make sure the bowl used to whip egg whites and whisk are free of any oils, or the egg whites will not beat into stiff peaks!
I use a kitchen scale to weigh the batter in pans to make sure all layers are evenly distributed.
No buttermilk? Make your own substitute by pouring 1 tablespoon of lemon juice (fresh or bottled) or white vinegar into a one cup measure. Fill the measuring cup with milk. Let sit for 5-10 minutes on the countertop. You may also use ½ cup of plain Greek yogurt mixed with ½ cup of milk (skim or whole doesn't matter) whisk until smooth. This works best when the milk is at room temperature. If you don't want to wait, heat the milk up in the microwave just until room temp or barely warm, then proceed with instructions for making buttermilk.
No cake flour? Measure out one cup of all purpose flour into a bowl. Remove 2 tablespoons flour and replace back into flour container. Add 2 tablespoons cornstarch to the bowl with flour. Place the flour and cornstarch into a sifter or a small wire mesh strainer. Sift flour and cornstarch mixture together. Use as directed in recipe to equal one cup of cake flour.
Each oven bakes differently. If your oven bakes hot on the top, lower the rack to the bottom third of your oven. If your oven bakes hotter on the bottom, raise the rack a bit. You may also need to adjust the oven temperature more or less 25 degrees. This cake may take as few as 20 minutes to bake and for some, closer to 25.