Defrost the kale in the broth at medium heat. Peel and chop the onions. Wash the Kasseler, dab dry and cut into cubes. Heat the lard in a pan, fry the diced onions and the smoked pork in it while turning and then add to the kale.
Covered kale and simmer at low heat for about 1 hour, stirring from time to time. In the meantime peel and wash the potatoes. Heat the oil in a pan, add the potatoes and fry for about 20 minutes, turning.
Season potatoes with pepper, coarse salt and sugar. Cut the carbanossis into slices and add them to the kale 5 minutes before the end of the cooking time. Season the kale with pepper and sugar. Arrange potatoes and kale on plates.
Add mustard.