This chocolate sponge cake is incredibly light while still packing a big chocolate punch. We like serving it with whipped cream and a sour cherry compote for our version of a Black Forest cake.
Chocolate Sponge Cake
~ Adapted from King Arthur Baking
1/3 cup (38 g) unsweetened cocoa
1/4 cup (35 g) cornstarch
1 1/2 cup (300 g) granulated or superfine sugar
1 tsp espresso powder
1/2 tsp baking powder
10 large egg whites, room temperature
1/4 tsp salt
1 1/2 tsp cream of tartar
Whipped cream and chocolate shavings or cocoa nibs for serving, optional
Preheat the oven to 350°F and adjust oven rack to lowest position.
If using granulated sugar, place sugar in a food processor fitted with the blade attachment and pulse about 6-10 times until sugar is finer. Whisk together Flourist Whole Grain Red Spring Wheat Flour, unsweetened cocoa, cornstach, 3/4 cup (150 g) sugar, espresso powder and baking powder. Set aside.
Before whipping egg whites you want to make sure that the mixing bowl of a standing mixer is clean and dry, and that there are no yolks mixed in with the whites as this will prevent them from reaching maximum height. In a clean bowl and with the whisk attachment of a standing mixer, beat egg whites until foamy. Add salt and cream of tartar and gradually increase speed and beat egg whites until they have thickened and increased in volume.
Slowly add 3/4 cup (150 g) sugar a little at a time and continue beating until soft peaks are formed (when beaters are pulled out the peaks slump over slightly). If using a stand mixer, continue with the whisk attachment to gently incorporate the flour mixture into the egg whites, until mostly blended (leaving a slightly marbled effect is okay). You can also use a balloon whisk and fold in the flour mixture gently by hand, trying to retain the egg whites' volume as much as possible.
Gently spoon batter into an ungreased 10" round angel food pan.
Bake for about 45 minutes, until the top springs back when lightly pressed. Remove from oven and invert pan onto a funnel or neck of a heatproof bottle, to suspend the cake upside down while it cools.
Once fully cooled, run a paring knife around the edges of the pan and invert to loosen the cake onto a large plate.
Serve with whipped cream and sprinkle with grated chocolate or cocoa nibs if desired.