Separate the eggs. Beat the egg yolks with water and sugar (100 g) until white and creamy. Mix in the nuts, vanilla flavor and baking powder one after the other. Beat the egg whites with 50 g sugar until stiff and fold in carefully.
Fill the dough in the form or on the baking sheet (both with parchment paper) (wet parchment paper is easier to shape). Bake the dough in the preheated oven for 45 minutes (in the tin) or 20 minutes (on the baking sheet) at 170 ° C.
Turn the finished biscuit out onto a damp cloth or grid and slowly remove the baking paper. Fill the cake as desired.