Peel the onions. Dice 1 onion finely, cut 2 onions into rings and dust with flour. Wash and peel the potatoes thoroughly and cook them in boiling salted water for about 25 minutes.
Heat 1-2 tbsp. oil in a casserole dish, fry diced onion in it until transparent, turning. Add sauerkraut, juniper berries and bay leaves, season with salt, pepper and sugar. Fry for 3-4 minutes while turning. Deglaze with apple juice, bring to the boil, cover and stew for about 20 minutes.
Peel the skin off the sausage. Cut the sausage into slices. Heat milk and butter in a small pot. Drain the potatoes. Mash them with a potato masher and add the hot milk. Season with nutmeg and salt. Keep warm
Wash parsley, shake dry and chop finely. Heat clarified butter in a pan and fry the onion rings until golden brown, turning them over. Brush a pan thinly with 1 tbsp. oil, heat it up and fry the sausage slices for about 1 minute on each side.
Arrange sauerkraut, slices of sausage and mashed potatoes on plates. Sprinkle potatoes with onion rings and parsley