Baking: Chocolate cheesecake (Russischer Zupfkuchen)

Dough
200 gbutter
150 gsugar
350 gflour
30 gcocoa powder
1 sachetbaking powder
1egg

Filling
180 gsoft butter
200 gsugar
4eggs
500 glow-fat quark
3 sachetsvanilla sugar
30 gcornflour