Warm milk and crumble yeast into it and dissolve it. Put flour, 1 egg, 50 g fat, sugar, salt and yeast milk into a bowl and work into a smooth dough using the dough hooks of the hand mixer.
Cover and leave to rise for about 30 minutes in a warm place. In the meantime peel onions and cut them into rings. Cut the bacon into cubes. Heat 25 g fat in a pan. Brown the onion rings and caraway seeds in it, remove.
Brown the bacon cubes in the pan and let them drain on kitchen paper. Cut the chives into small rolls. Mix sour cream, 2 eggs and chives, up to 1 tablespoon, season with salt and pepper.
Grease a fat pan (28 x 34 cm) and dust with flour. Knead the yeast dough once, roll it out (30 x 36 cm) and place it in the fat pan, prick it several times with a fork. Spread the onion and bacon on top and pour the egg cream over it.
Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 25-35 minutes. Remove from the oven and allow to cool slightly. Cut into pieces and sprinkle with 1 tablespoon of chives.