Select the kale and wash thoroughly. Put the cabbage in a pot of boiling water, cover and cook for 5-10 minutes, then let it collapse. Pour onto a sieve, let cool and chop coarsely.
Onions peel and cut into fine slices. Heat 50 g clarified butter in a pot and sauté the onions in it. Wash the Kasseler and add them together with the kale. Add 3/8 -1/2 litres of water, bring to the boil, cover and stew for about 1 hour.
Place the ham and chilli peppers on the kale about 15 minutes before the end of the cooking time and cook at the same time. Wash the potatoes and cook in plenty of boiling water for 15-20 minutes. Drain the potatoes and remove the skin.
Wash duck breast, dab dry and cut the skin crosswise. Heat oil in a pan and fry the duck breast first on the skin side for about 5 minutes. Then turn, season with salt and pepper and fry over medium heat for 8-10 minutes.
Turn again in between. Wrap duck breast in aluminium foil and let it rest for about 5 minutes. Heat the remaining clarified butter in a pan and fry the potatoes until golden brown while turning. Season with salt and pepper.
Also season the kale with salt, pepper and mustard. Remove the pork loin from the bone and cut the meat into thin slices. Duck breast and ham-pepperlings also cut into slices.
Arrange kale, meat and sausage on a plate and add the roast potatoes separately.