Preheat the oven to 170 degrees top / bottom heat. Butter a 26 cm springform pan and line the bottom with baking paper. Seal the edge with aluminum foil in order to keep the water bath outside later.
Melt the butter and crumble the biscuits. Mix together all the ingredients for the base and press them into the mold so that a 2 cm high edge is created.
Beat the cream cheese, sour cream, sugar and vanilla sugar until smooth. Add the eggs one at a time and stir in one at a time. Finally add the milk and flour to the mixture. Spread the mixture on the biscuit base.
Now place the mold in a deep fat pan and fill it with boiling water. Bake the cheesecake in a water bath for an hour.
After baking, let the cake sit in the oven for 15 minutes with the heat turned off. Then take the pan out of the water bath, remove the aluminum foil and let the cake cool down completely.
12 Prick circles of the same size from the cooled cake.