Drain the cherries, sprinkle with 30 ml of kirsch. Melt the couverture, let it cool down a little. Cream fat, sugar and salt with the whisk of the hand mixer. Stir in eggs bit by bit. Mix flour and baking powder, alternately stir into the fat-sugar mass with the milk.
Halve the dough, fold the marinated cherries into one half. Stir the melted chocolate, 1 teaspoon of cocoa and vanillin sugar into the other half. Grease the ring cake tin (2 litres capacity) well, dust with flour. Pour in light dough, add dark dough. Pull a fork spirally through both layers. Bake in the preheated oven (electric: 175 °C/ gas: level 2) on the lowest rack for approx. 80 minutes. Allow to rest briefly in the pan, then turn out onto a cake rack and allow to cool. Stir icing sugar with remaining kirsch and 20 ml water to a smooth glaze. Colour one half of the icing with remaining cocoa. Coat the cake alternately with white and brown icing to create a marble effect.
Bake in the preheated oven (electric: 175 °C/ gas: level 2) on the lowest rack for approx. 80 minutes. Allow to rest briefly in the pan, then turn out onto a cake rack and allow to cool. Stir icing sugar with remaining kirsch and 20 ml water to a smooth glaze. Colour one half of the icing with remaining cocoa. Coat the cake alternately with white and brown icing to create a marble effect. Use a peeler to remove curls from both types of chocolate and sprinkle them on the cake. Let the icing dry