Cream fat, sugar and vanilla sugar with the whisk of the hand mixer. Stir in the eggs one by one. Mix flour and baking powder and stir in alternately with the milk. Grease 4 preserving jars and dust with flour.
Fill the dough evenly into the glasses. Bake the glasses in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: stage 2) for approx. 45 minutes. Take the cake out of the oven and, if you want to keep it for a longer time, close the lid.
After about 10 minutes, turn the cake over and let it cool on a cake rack. In the meantime, roughly chop the chocolate coating and melt over a warm water bath. Spread on a marble slab (or something else suitable) and put in a cool place.
Mix lemon juice and icing sugar. Colour pink with a few drops of food colouring. Cover cooled cakes with icing and let them dry. Use a spatula to scrape chocolate rolls from the marble top and decorate the cakes with them.