Wash the meat and pat dry. Place on the fat pan of the oven. Pour on 1/2 l water. Roast in the preheated oven (electric cooker: 175 °C/circulating air: 150 °C/gas: level 2) for approx. 1 1/4 hours
Onions peel, finely dice. Fry them in hot oil in a pot until translucent. Take out onion cubes, up to approx. 2 tablespoons, and let cool down. Add sauerkraut, bay leaf, juniper and peppercorns to the pot and fry. Deglaze with sparkling wine and grape juice. Bring to the boil, cover and stew for 35-40 minutes
Mix cooled onions, eggs, breadcrumbs and mustard. Season with salt, pepper and sugar. Spread the onion mixture on the meat. Turn up the oven (electric cooker: 200 °C/circulating air: 175 °C/ gas: level 3). Fry the pork loin for approx. 20 minutes
Wash the grapes, possibly halve them and remove the seeds. Add to the cabbage about 10 minutes before the end of cooking time. Keep the cured pork warm. If necessary, add a bit of pork stock to the cabbage, season to taste. Serve everything. Served with: parsley potatoes