Chop the chocolate and melt it in a double boiler. Spread thinly on the baking paper. Put in a cool place.
Drain the cherries, but catch the juice. Mix 4 tablespoons of juice and starch until smooth. Bring the rest of the juice to the boil. Bind with mixed starch. Fold in the cherries, let the compote cool down.
Season the quark with sugar and lemon. Peel and slice the bananas and stir in. Layer with the compote in 8 glasses.
Remove the chocolate from the baking paper and decorate the dessert with it!