Mix the flour, cocoa powder, salt, sugar and vanilla sugar
Melt the butter and add to the flour mixture and process everything into crumble.
Chill the sprinkles for at least 1 hour.
Peel and core the apples and cut into pieces.
Drizzle with lemon juice.
Mix together the egg yolks, sour cream, powdered sugar and cinnamon.
Grease a 26 cm springform pan and fill in half of the chocolate sprinkles and press down to a bottom.
Spread the apple pieces on top.
Pour the creamy cream on top and spread the remaining crumble on top.
Bake the cake in a preheated oven at 160 ° for about 40 minutes.
Let cool and serve.