Mix 1 egg with butter and 80 g sugar until frothy. Sift the flour, mix with the baking powder, work with the egg mixture into a dough and roll it out thinly. Line the bottom and edge of a greased springform pan evenly with the batter.
Mix the sour cream, cream, 80 g sugar, custard powder and 1 egg with a whisk until smooth. Drain the cherries well and fold in carefully.
Pour the whole mixture into the springform pan lined with the batter.
Bake in a preheated oven (180 ° C) for about 40 minutes.