for the dough:
3 cups all-purpose flour
3 teaspoons baking powder
⅓ cup cocoa powder, unsweetened
1 cup granulated sugar
1 teaspoon vanilla extract
1 egg, room temperature
¾ cup + 2 tablespoon butter, room temperature
for the filling:
1 ⅛ cup butter, melted
2 ¼ cups plain quark
1 cup cane sugar
2 tsp. vanilla extract
⅓ cup cornstarch
1 teaspoon powdered sugar (optional)
1. In a large bowl mix flour, baking powder and cocoa powder. Add sugar, vanilla extract, egg, and butter. Mix on low speed first and then on high speed to get a smooth dough. Wrap in plastic wrap and let chill in the fridge for 30 minutes.
2. For the filling, melt the butter and allow it to cool. Grease a 9-inch springform tin and set aside. Preheat the oven to 350°.
3. Roll out half of the dough to the size of the bottom of the baking pan. From the remaining dough form a long roll, place the roll on the edge of the pastry and press to the sides of the spring form tin. Make sure to keep some of the dough for the topping.
4. In a large bowl, mix the quark with sugar, vanilla extract, eggs, cornstarch, and the melted butter until well combined. Pour the mixture on top of the prepared dough and smooth out. Tear the remaining dough into small pieces and spread them on top of the filling. Bake the cake for about 60-65 minutes or until golden yellow. Let cool completely on a wire rack before serving. Dust lightly with powdered sugar.