Beat the butter and sugar until frothy. Then add the eggs and yolks. Mix the flour with the baking powder and the pulp of the vanilla pod and fold in. Spread the dough in a springform pan. For the nut crust, stir the egg with the egg white and sugar until foamy, fold in the ground nuts and spread the mixture on the dough. Bake the cake in the preheated oven (electric stove 175 degrees, convection 160 degrees, gas stove level 2) on the lower shelf for approx. 50 minutes.