For the dough, add butter, sugar, flour, cocoa powder, baking powder and an egg to the mixing bowl, process 30 sec./ speed 6 to a dough and remove from the mixing bowl. Press 2/3 of the mixture into a springform pan lined with baking paper and pull up one edge.
For the filling, add butter, sugar, eggs, low-fat quark, vanilla sugar and vanilla pudding powder to the mixing bowl and stir for 40 sec./ speed 5, then place on the bottom. Tear up the remaining dough and spread it on the filling.
Bake in the preheated oven at 180 ° for approx. 60 minutes.