Beat the soft butter / margarine with the sugar, vanilla sugar and egg yolk until very frothy. Add the quark, semolina and the pudding powder to the dough (round off with Grand Marnier or rum if necessary!) And stir well.
Carefully fold in the egg white, beaten until stiff with a pinch of salt.
Grease the springform pan (26cm) and sprinkle with breadcrumbs. Pour in the curd mass.
Scald the fresh peaches briefly with hot water, peel them and cut them into eighths. Distribute evenly on the quark dough. Bake the cake for about 60 minutes.
Then brush the still warm cake with warmed peach or quince jelly.