I baked this mocha cake recipe in response to a reader's request for a dessert like the one he remembered from his younger days spent in France. I know I can't live up to a childhood memory, but hopefully this cake comes close.
Gateau Moka is still popular, and you are likely to find slices of it served in a salon de thé or a pâtisserie.
Recipe Notes for Mocha Cake
A genoise cake is made with no leavening other than beaten eggs. Please don't be put off by the "risk" of making a cake this way, all you need is a mixer (I did it with a hand mixer) and a bit of patience.
Since this mocha cake recipe contains no butter, it can take the rich butter cream frosting without becoming overwhelming. You can make the cake layer ahead of time, wrap it in plastic and store it at room temperature for two or three days.
I made this mocha cake in one 10 inch round cake pan, then sliced it into three layers to frost. You could also make a two layer cake by baking it in two 9 inch cake pans. The results will be a slightly higher cake then
the one pictured here.
French buttercream frosting is made with lots of egg yolks, which will need to be as fresh as possible. It is a little tricky to make, but well worth the effort. This is not a good frosting to make on hot or humid
days. It should be at room temperature for easy spreading and decorating, but then should be immediately refrigerated.
Preheat oven to 350°F. Butter and line the bottom of a 10 inch round cake pan with parchment paper.
Sift and measure the flour so you have it ready once you start beating. Measure the sugar and set to the side as well.
Crack the eggs into an extra large mixing bowl. Using a hand or stand mixer, beat the eggs on high for about 7 minutes or until they are very fluffy and light colored. Continue beating and add the sugar one tablespoon at time, making sure each tablespoon is fully incorporated before you add the next. Adding all of the sugar should take about 5 minutes. Beat in the vanilla extract.
Turn off the mixer and sift half of the sifted flour into the mixing bowl. Using a spatula, fold in the flour. Once it is nearly incorporated sift the rest of the flour into the mixing bowl and fold it in as well. Use a light touch and stop as soon as the flour is incorporated.
Pour the batter into the prepared cake pan. Bake at 350°F for 25 to 30 minutes or just until a toothpick stuck in the middle of the cake comes out clean. Do not overbake.
Remove the cake from the oven and allow to cool 10 minutes. Turn the cake out onto a wire cooling rack, remove the waxed paper, and allow the cake to cool completely.
Coffee Flavored Syrup
1/3 cup sugar
1/4 cup water
1 tablespoon coffee extract
Place the sugar and water in a small saucepan. Bring to a boil on medium heat, then boil for two minutes. Remove from heat and stir in coffee extract.
French Buttercream Frosting
9 ounces (18 tablespoons or 2 1/4 sticks) very soft butter
8 egg yolks
1/4 cup water
1 1/4 cups sugar
1 tablespoon coffee extract
Work the butter into a soft cream by beating it with a wooden spoon. Set aside.
Place the egg yolks in a large mixing bowl and beat for about 2 minutes.
Put the water in a small saucepan and add the sugar. Without stirring, bring to a boil on medium heat. Boil for a few minutes until the syrup reaches 240°F. Remove immediately from heat.
Beating the egg yolks continually, slowly add the hot syrup, aiming it in a thin stream between the side of the mixing bowl and the beating whisk. When all of the syrup has been incorporated continue beating until the mixture has cooled to room temperature. This will take several minutes at least.
Next add the butter 1 tablespoon at a time, beating well after each addition. Once all of the butter has been incorporated, add the coffee extract. Continue beating until the buttercream attains frosting consistency. Don't dispair if it seems runny, just keep beating.
1 cup sliced almonds (about 3 ounces)
Spread the almonds on a baking sheet and bake at 400°F for 2 to 4 minutes. Watch out - these toast quickly.
Using a long serrated knife, carefully cut the genoise horizontally into three layers (two layers would be fine as well). Brush the crumb side of each layer with the coffee syrup.
Place the first layer, crumb side up on a serving dish and slide some pieces of wax paper under the edges of the cake to keep the dish clean for serving.
Frost the layer with a generous cup of frosting, then add the next layer and repeat the frosting. Add the last layer with the crumb side down so you have a smooth surface for the top. Frost the sides (lightly) and the top of the mocha cake with about 2 cups of frosting, leaving enough frosting for the final decoration.
Using your fingers, press the toasted almonds into the side of the mocha cake and sprinkle some on top too if you wish. Fill a decorating bag with the rest of the frosting and make a pretty pattern on the top of the cake. Keep refrigerated until ready to serve.
The word mocha comes from the Yemen city of the same name. With a port on the Red Sea, Mocha has been exporting coffee beans throughout the world for centuries. When used to describe a recipe, mocha indicates that
you will find coffee as a dominate flavor.