Fill flour, 60 g soft butter, 1 egg and 1 teaspoon salt into a mixing bowl. Warm milk lukewarm, dissolve yeast in it. Pour into the flour and knead. 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 the marjoram and remove the leaves. Heat 50 g butter in a pan. Leave the bacon out, add the onions and steam for about 8 minutes. Season with salt, pepper, caraway and marjoram. Knead yeast dough briefly and roll out on a greased baking tray. Spread onions on top. Mix 3 eggs and sour cream. Season with salt and pepper.
Knead yeast dough briefly and roll out on a greased baking tray. Spread onions on top. Mix 3 eggs and sour cream. Season with salt and pepper. Dribble evenly over the cake. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 30 minutes