Chocolate Sponge Cake Recipe


The beauty of a sponge cake is that you only need the most basic of ingredients. The tricky part is to make a sponge with good volume, for while a butter cake relies on baking powder to do this job, a sponge cake relies solely on the beaten egg. When I consulted ‘The Oxford Companion to Food’ on this subject Alan Davidson aptly explains that a good sponge “starts with prolonged whisking of eggs and sugar which incorporates air, distributing it through the mixture as tiny bubbles. During baking the air expands, leavening the mixture with a network of little holes surrounded by walls of coagulated egg proteins; hence the name ‘sponge cake’.”  This explanation tells us how important technique is and that once you have perfected the beating of the yolks and whites to full volume and then are able to add the two together without deflating the batter, you will produce a perfect sponge cake each and every time.

Now, this chocolate sponge cake is a little different from most in that it does not contain flour which makes for a very light and moist cake; more like a baked mousse or as Rose Levy Beranbaum puts it “this is more a flourless souffle than a cake”.  It is also different in that it is baked in a sheet pan, not a cake pan, so you do not have to worry about it deflating and also don’t worry if the sponge cracks when you roll the cake around the filling as this is normal. The chocolate flavor in this cake is wonderful which allows us to fill it with a variety of flavors.  Because of its light texture and taste I like to pair it with one of the Whipped Cream Frostings; either plain, chocolate, raspberry or strawberry. You may also want to serve it with the strawberry or raspberry sauce.

Chocolate Sponge Cake: Preheat oven to 350 degrees F (180 degrees C) and place the oven rack in the center of the oven.  Butter, or spray with Pam, a 17 inch (43 cm) by 12 inch (30 cm) jelly roll pan. Line the pan with parchment paper and then butter and flour the paper (or spray with Baker’s Joy).  Set aside.
While the eggs are still cold, separate the eggs, placing the whites in one bowl and the yolks in another. Cover with plastic wrap and bring to room temperature before using (takes about 30 minutes).
Meanwhile melt the chocolate in a stainless steel bowl set over a saucepan of simmering water. Set aside.
In the bowl of your electric mixer (or with a hand mixer) place the egg yolks and 1/4 cup (50 grams) of sugar and beat until this mixture is light and fluffy (about five minutes).  (When you slowly raise the beaters, the batter will fall back into the bowl in a slow ribbon.) Beat in the vanilla extract. Add the melted chocolate and beat only to combine. Set aside while you beat the egg whites.
In a clean mixing bowl, with the whisk attachment, beat the egg whites until foamy. Add the cream of tartar and beat at medium-high speed until soft peaks form. Gradually beat in the remaining 2 tablespoons (28 grams) of sugar until stiff peaks form.
Gently fold a small amount of the egg whites into the egg yolk mixture using a rubber spatula or whisk to lighten the batter.  Fold in the remaining whites just until incorporated.  Don’t over mix or the batter will deflate. Spread the batter evenly into the prepared pan with an offset spatula. Bake until the cake is puffed, has lost its shine, and springs back when gently pressed, about 15-17 minutes. Remove from oven and place on wire rack to cool. Cover the cake with a clean, slightly damp towel.

Whipped Cream: In a large mixing bowl place the whipping cream, vanilla extract, and sugar. Beat the mixture until stiff peaks form.
Once the cake has cooled, spread with the whipped cream and gently roll the cake, peeling off the parchment paper as you roll.

Can be stored in the refrigerator for up to five days.
Source:
Beranbaum, Rose Levy. The Cake Bible. William Morrow and Company, Inc. New York: 1988.

Chocolate Sponge Cake:

1/4 cup (50 grams) plus 2 tablespoons
(28 grams) granulated white sugar
6 large eggs, separated
1/2 teaspoon pure vanilla extract
4 ounces (112 grams) bittersweet or semisweet chocolate, chopped in small pieces
3/4 teaspoon cream of tartar
Whipped Cream:
1 cup (240 ml) heavy whipping cream
1/2 teaspoon pure vanilla extract
1 tablespoon (15 grams) granulated white sugar