Cleaning the savoy cabbage. Cut cabbage into quarters, remove stalk. Cut cabbage into strips of about 2 cm width. Peel and halve onion and cut into small cubes.
Heat clarified butter in a pot. Fry diced onions and caraway seeds. Add white wine and cook for about 3 minutes in an open pan. Meanwhile peel and wash the potatoes and cut them into pieces of about 3 cm.
Add potatoes, stock and cabbage to the pot and bring to the boil. Pour into an oval form or roaster (approx. 3 litres capacity).
Wash thyme, remove leaves and chop coarsely. Mix with both types of mustard. Stir in breadcrumbs. Season mass with salt, pepper and honey and mix. Beat egg whites until stiff and fold in.
Wash the cured pork loin and pat dry with kitchen paper. Cut off the upper firm skin and add to the cabbage. Dab meat dry again, pour mustard mixture on the meat and wave it with a knife.
Place the meat on the vegetables in the mould.
Place the mould on the oven rack in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer), cook the meat for approx. 1 hour. Wash parsley, pluck off leaves and chop coarsely.
When the cooking time is over, remove the meat from the oven and let it rest for about 5 minutes. Remove meat cuts from the cabbage. Stir half the sour cream into the cabbage, season with salt, pepper and nutmeg.
Arrange the meat in pieces or cut up on the vegetables. Add the rest of the sour cream.