Cream fat, sugar and 1 packet of vanilla sugar with the whisk of the hand mixer. Separate the eggs. Stir the egg yolks into the fat-sugar mixture. Mix flour, starch and baking powder.
Mix espresso powder and 1 teaspoon of hot water. Add cream and stir alternately with the flour mixture into the fat-egg yolk mixture. Beat the egg white until stiff and fold in. Line the bottom of a springform pan (26 cm Ø) with baking paper.
Pour in the dough and smooth it down. Bake in the preheated oven (electric: 175 °C/ gas: level 2) for 20-25 minutes. Let them cool down. Beat the quark, mascarpone, remaining vanilla sugar and mocha liqueur until creamy.
Spread on the cake in a wave shape and decorate with chocolate rolls and mocha beans. Makes about 12 pieces.