Peel the apples. Roughly grate 5 of them, cut one into pieces. Mix the apples with the amaretto. Mix the butter, sugar and vanilla sugar until frothy, gradually stir in the eggs and add the cinnamon powder. Mix the flour with the baking powder and stir in. Finally mix in the almonds and grated apples. It should be a viscous dough, add flour if necessary. Pour the mixture into a greased springform pan and bake in a preheated oven at 175 degrees (convection) for about 40 minutes. If you want, you can sprinkle the cake with powdered sugar after baking.