Put flour, soft fat, egg and approx. 1 teaspoon salt in a mixing bowl. Warm milk, stir in yeast and pour into the flour. Knead everything, cover and leave to rise in a warm place for about 30 minutes. In the meantime peel onions and cut them into rings. Dice bacon finely.
Wash marjoram, pluck off leaves and chop. Heat the fat in a pan, fry the bacon and add the onions. Steam for 5-10 minutes. Season with salt and pepper, stir in caraway and marjoram. Leave to cool a little. Grate the cheese roughly. Knead yeast dough briefly and roll out on a greased baking tray. Spread onion mixture on top and sprinkle with cheese. Mix eggs, crème-fraîche, little salt, pepper and nutmeg. Pour over the cake.
Grate the cheese roughly. Knead yeast dough briefly and roll out on a greased baking tray. Spread onion mixture on top and sprinkle with cheese. Mix eggs, crème-fraîche, little salt, pepper and nutmeg. Pour over the cake. Bake in the preheated oven (electric oven: 200°C/ gas: level 3) for about 30 minutes. Cut into 12-16 pieces while still warm and serve