Drain the cherries and drizzle with 30 ml of kirsch. Melt the couverture. Mix the fat, salt and sugar together. Stir in eggs one at a time. Mix the flour and baking powder and stir in alternately with the milk. Halve the dough and fold the cherries into one half. Stir the melted couverture, 1 teaspoon cocoa and vanilla sugar into the second half.
Grease the bundt pan and dust with flour. Pour in the light dough, top with the dark dough and use a fork to pull it spirally through both layers. Bake the cake in a preheated oven at 175 ° C top / bottom heat (150 ° C convection) for approx. 60-70 minutes (stick test).
Mix the icing sugar and remaining kirsch with 2 tablespoons of water until smooth. Color half of the topping with the remaining cocoa. Cover the cooled cake alternately with white and brown icing.