Preheat the oven to 175 ° C top / bottom heat. Grease a 30 x 40cm baking tray.
For the dough, beat the margarine, sugar, vanilla sugar and salt with the whisk of the hand mixer until frothy. Gradually stir in the rum and eggs and continue beating for a few minutes. Mix the flour, baking powder, cocoa and pudding powder and sieve in. Stir in briefly. Then spread the dough on the baking sheet and prebake for about 10 minutes.
In the meantime, beat the egg white with a pinch of salt until stiff and slowly add sugar, vanilla sugar and bitter almond flavor. Spread the egg whites evenly on the cake and bake for another 15 minutes until the meringue is light golden yellow.