Wash the kale and blanch briefly in boiling water in portions. Pour the cabbage onto a sieve, let it cool down a bit and chop it. Peel and chop onions. Heat lard in a pot.
Brown the onions in it. Add cabbage, 1/4 litre stock and bacon, bring to the boil and braise for about 1 hour. In the meantime wash potatoes and cook them in boiling water for about 20 minutes. 20 minutes before the end of the cooking time add cooked sausages to the kale and possibly add 1/8 litre stock.
Drain the potatoes, rinse and peel them. Heat clarified butter in a pan. Fry the potatoes in it, turning them golden brown, season with salt and pepper. Sprinkle sugar over them and let them caramelize.
Remove bacon from the kale and cut into slices. Season the kale to taste and arrange on plates with bacon, cooked sausage and caramel potatoes. Serve with mustard.