For the knuckles 2 onions peel and halve. In a large roaster or pot, boil up about 5 l salted water, peppercorns, cloves, 2 bay leaves and 4 juniper berries. Wash the knuckles and put them into boiling water.
Possibly pour on water to cover the knuckles. Simmer covered for about 2 hours.
For the sauerkraut, peel 2 onions, halve them and cut into strips. Heat the lard in a pot and fry the onions for about 4 minutes until transparent. Add the sauerkraut. Season with 4 juniper berries, 1 bay leaf, pimento, caraway and sugar.
Cover and stew for about 1 hour. After approx. 30 minutes, pour on approx. 1⁄4 l knuckle stock.
Clean or peel and wash the soup vegetables. Peel 1 onion. Dice everything roughly and spread it on the fat pan. Place in the hot oven (electric cooker: 200 °C/circulating air: 175 °C/gas: see manufacturer) on the lowest shelf.
Slide the grill grid over it. Put the knuckles on top and keep the stock. Fry for approx. 1 1⁄2 hours until crispy. After approx. 1 hour pour approx. 400 ml knuckle of pork stock into the vegetables.
For the mashed potatoes, meanwhile, peel, wash and halve the potatoes. Cook in salted water for about 20 minutes. Warm up milk and butter. Drain potatoes, add milk mixture, mash everything.
Season to taste with salt and nutmeg.
Brush knuckles with salted water and grill for 5-10 minutes. Remove the meat from the fat pan with a little stock and pour through a sieve. Fill up with stock to approx. 350 ml and bring to the boil. Stir 5 tbsp. stock and starch until smooth, thicken sauce with it.
Season to taste with salt and pepper. Arrange everything.