Wash the potatoes and cook in boiling water for about 20 minutes. Wash marjoram, shake dry and chop finely. Drain the sauerkraut in a sieve and squeeze it gently. Peel onions and cut into fine slices. Heat 20 g clarified butter, sauté the onions for about 5 minutes. Add the sauerkraut, bay leaf, stock and apple juice and steam for approx. 20 minutes
Wash the apples, grate them dry, quarter them, remove the core and cut the apple quarters into slices. Wash the smoked pork and cut into cubes. Clean, clean and quarter mushrooms. Season sauerkraut with salt, pepper and sugar
Heat the oil in a large pan, fry the mushrooms in it while turning, remove and let cool. Heat 20 g clarified butter in the pan. Sauté the smoked pork loin, add the sauerkraut, marjoram and apple slices, bring to the boil again and braise over medium heat for about 15 minutes.
Drain boiled potatoes, quench, peel and press through a potato ricer. Allow to cool slightly, knead with eggs and potato flour. Carefully knead the mushrooms. Season to taste with nutmeg, salt and pepper. Shape into 8 dumplings
Bring plenty of salted water to the boil and let the dumplings simmer for about 10 minutes at low heat. Lift out dumplings and let them drain. Remove the Kasseler-Sauerkraut pan from the heat and season again with salt and pepper. Arrange on plates