Mix the eggs, mineral water, sugar, oil, flour and baking powder together well and make a batter. Spread the dough on a deep, greased baking sheet (drip pan).
Bake in a preheated oven at 200 ° C for about 20 minutes.
In the meantime, whip the cream until stiff and gradually fold in the sour cream and vanilla sugar. Then pour the mixture on the baked and cooled base. Sprinkle with cinnamon and sugar.