Separate the eggs. Cream the egg yolks with the sugar, vanilla sugar and the Citro-Back.
Beat the butter in another bowl until fluffy. Mix the flour and the cornstarch. Then sift onto the butter and stir in. Add the egg yolk mixture and mix in thoroughly. Using a mixer, vigorously stir in the sweet cream. Beat the egg whites until stiff and gently fold into the batter. Line the bottom of a springform pan with baking paper. Pour 2 ladles of batter into it and smooth it out.
Bake in the preheated oven with the broiler on for about 2 to 3 minutes.
On top of the browned layer, pour batter again, smooth it out and bake this layer as well for 2 to 3 minutes. Bake the dough in this way little by little. Let the cake cool and cut it into small corners. Finally, dip the corners in melted chocolate icing. Tip: White icing also tastes very good!
