I admit that I am late to loving coconut. I used to find the flavor overpowering in an “Am I eating sunscreen?” kind of way, but over time, I have learned to love it in its many forms.
I especially like thick, flaked coconut, which adds a little drama and a lot of delicious crispiness to the outside of this cake, which is made from light, sponge cake layers soaked in coconut rum syrup, and topped with Swiss buttercream. The whole thing is soft and squishy in the most comforting way.
In the taxonomy of sponge cakes, this one falls somewhere between a chiffon cake and a Génoise because it uses whole eggs and oil, but no chemical leavener. Instead, its lift comes only from the air incorporated when whole eggs are whipped with sugar.
I have a personal aversion to folding egg whites into cake batter, so unlike most sponge cakes, this method calls for whipping whole, room temperature eggs along with sugar (rather than separating the eggs, then folding the whipped egg whites in at the end)—and to great effect.
If you have a stand mixer, add the sugar, eggs, and extract to the bowl, crank it up, and walk away for a few minutes. After about 7 minutes of whipping, the mixture will grow so much it will threaten to fly right out of the bowl—that’s when you know it is ready.
If you have a 4 1/2-quart mixer, you may need to transfer the egg mixture into your biggest mixing bowl before folding in the flour. It’s always best to use a big, wide bowl when folding ingredients together to lower your chances of deflating the batter too much.
Putting this cake together is super forgiving because it will eventually be covered in toasty flaked coconut, so you don’t have to worry too much about your frosting technique. Just make sure there is a nice, even-ish coating of frosting all around the sides and cover all of your “mistakes” with crisp coconut.
And if the top isn’t looking so great, add some coconut there, too. Like most frosting covered cakes this one is definitely best served at room temperature.
For the cake:
- 10 large eggs, at room temperature
- 1 1/2 cups sugar
- 1 tablespoon vanilla extract
- 1/2 cup canola or grapeseed oil
- 1 3/4 cups cake flour, sifted
- 1 teaspoon kosher salt
For the coconut rum syrup and buttercream:
- Coconut Rum Syrup:
- 1/3 cup water
- 1/3 cup sugar
- 2 tablespoons rum
- 1/3 cup shredded or flaked coconut
- 5 egg whites
- 1 1/4 cups sugar
- 1 pound unsalted butter, soft but cool
- 2 teaspoons vanilla extract
- 1 teaspoon coconut extract (optional)
- 2 1/2 cups flaked coconut, toasted