Peel onions and cut them into rings. Quarter white cabbage, remove stalk and cut finely.
Heat butter in a pot and fry onion rings until translucent. Add white cabbage and fry them 2 minutes. Add soup, season with salt and pepper and let all simmer covered about 15 minutes. Add soft cheese and 1 tbsp. parmesan and melt them. Remove dark green from spring onions, cut other parts in thin slices. Some minutes before serving soup stir in spring onions and parsley. Put soup into soup plates and sprinkle with the rest of parmesan.