Separate the eggs, place one egg white each in a container (e.g. cup). Knead flour, fat, sugar, egg yolk, baking powder and vanillin sugar to a smooth dough. Quarter the dough. Grease a springform pan (26 cm Ø) and roll out 1/4 of the dough on it. Beat 1 egg white until stiff, spread on the base and sprinkle with 1/4 of the sugar and 1/4 of the flaked almonds.
Bake in the preheated oven (electric: 200 °C / gas: level 3) for 10-12 minutes. Carefully remove the pastry base from the springform pan and let it cool down. In the meantime, bake the remaining dough one after the other as above. Whip the sour cream with the whisks of the hand mixer until stiff and spread evenly on three bases. Place on top of each other, place the last cake layer on top and leave to rise for 2 days