Mix the butter, sugar, vanilla sugar, a pinch of salt and the egg until frothy. Then add flour, brook powder and cinnamon and use the mixer whisk to make crumbles.
Line the bottom of a springform pan (size 26) with baking paper and grease the edge, then spread about half of the crumble on the bottom and press down.
Spread the applesauce on the bottom. Peel, core and eighth the apples, then spread over the applesauce.
Stir the brittle into the remaining crumble and then spread them over the apples.
Bake the cake at 180 degrees top / bottom heat on the middle rack for 45-50 minutes
(If you like, you can also stir raisins or cranberries into the applesauce. Or it is also very tasty if you add 2 tablespoons of cocoa to the batter).