This is a German cake, named after a special liquor made in the Black Forest region of Germany. I have to admit I omitted this apparently key ingredient. It's a basic chocolate genoise cake, filled and covered with whipped cream. I used sour cherries for the middle and glacé cherries for the top, although it's up to you which type of cherries you want to use.
For the chocolate genoise:
42 grams hot melted unsalted butter
1 teaspoon pure vanilla extract
1/2 cup (65 grams) cake flour
1/3 cup (30 grams) unsweetened regular or Dutch-processed cocoa powder
4 large eggs
2/3 cup (135 grams) granulated white sugar
Preheat oven to 175 degrees C. Butter, or spray with a vegetable spray, a 23 cm round cake pan and then line the bottom of the pan with parchment paper.
In a small bowl, combine the melted unsalted butter with the vanilla extract. Keep this mixture warm. If needed, re-warm for a few seconds just before using.
In a medium bowl sift together the flour and cocoa powder. Set aside.
In a large heatproof bowl whisk together the eggs and sugar. Place the bowl over a saucepan of simmering water. Whisking constantly, heat the eggs and sugar until lukewarm to the touch (this will take approximately 5 minutes depending on the temperature of the eggs and the simmering water). Remove from heat and transfer the egg mixture to the bowl of your electric mixer. Beat on high speed until the egg mixture has cooled, tripled in volume, and looks like softly whipped cream. This will take approximately 5 minutes and the batter is beaten sufficiently when the batter falls back into the bowl in a ribbon-like pattern.
Then sift about one-third of the flour mixture over the whipped eggs and fold in using a large rubber spatula or whisk. Fold in half of the remaining flour, and then fold in the rest. Do not over mix or you will deflate the batter. Then take about 1 cup of the batter and fold it into the hot butter mixture with a small spatula. (This will lighten the butter mixture and make it easier to incorporate into the egg batter without deflating it.) When completely combined, use a spatula to fold the butter mixture completely into the rest of the egg batter. Pour the batter into your prepared pan, smoothing the top.
Bake until the cake shrinks slightly from the edges of the pan and the top springs back when lightly pressed (about 20 - 25 minutes). Cool on a metal rack. When the cake has cooled completely, run a small knife or spatula around the edges to release the cake.
For the whipped cream filling:
3 cups (600ml) whipping cream
3 tablespoons sugar
1 teaspoon vanilla extract
Mix the cream, sugar and vanilla in a mixing bowl. Whisk with an electronic whisk until you get stiff peaks (it will be piping consistency).
For the filling/topping:
1/2 cup black/sour cherries in syrup
Glacé cherries to top
75 grams plain chocolate
Melt the chocolate over a pan of boiling water. Spread over a piece of parchment paper, then top with another piece of parchment paper. Roll and put in the freezer for 20 mins, or refrigerate for at least 2 hours. Unroll swiftly to release the chocolate shards.
When the genoise has cooled, split and fill with whipped cream and cherries.
Decorate with whipped cream, glacé cherries and chocolate shards.
Source: Genoise from Joy of baking