Cut the fish into 4 equal pieces, sprinkle with lemon juice and salt. Cover the fish and put it in a cool place. Peel onions and chop 2 onions roughly. Clean and peel the carrots and cut them into fine slices. Heat 20 g fat in a pan and fry the onions in it. Add the sauerkraut, carrots, bay leaf and peppercorns and braise while stirring occasionally until the cabbage begins to brown.
Season sauerkraut with salt and pepper. Peel and wash the potatoes and cook in plenty of boiling salted water for about 5 minutes. Drain. Finely dice the remaining onion. Wash dill, dab dry and chop finely, except for something for garnishing. Heat 15 g fat in a pot and fry the onion in it until transparent. Dust with flour, sweat it and deglaze with stock and cream while stirring. Let the sauce simmer for 3-4 minutes. In the meantime cut potatoes into slices. Dab fish dry. Heat remaining fat in a pan and fry the fish pieces from one side briefly and hot. Set aside.
Dust with flour, sweat it and deglaze with stock and cream while stirring. Let the sauce simmer for 3-4 minutes. In the meantime cut potatoes into slices. Dab fish dry. Heat remaining fat in a pan and fry the fish pieces from one side briefly and hot. Set aside. Stir mustard and dill, except for a little bit for sprinkling, into the sauce and season with salt and pepper. Put almost half of the potatoes in a greased casserole dish and pour 1/3 of the sauce over them. Spread the sauerkraut on top and place the remaining potatoes in flakes on the edge of the dish. Place fish slices on top of the sauerkraut and pour the rest of the sauce over them. Bake in the preheated oven (electric cooker: 200 °C/ gas: level 3) for 25-30 minutes. Sprinkle with remaining dill and serve garnished
Stir mustard and dill, except for a little bit for sprinkling, into the sauce and season with salt and pepper. Put almost half of the potatoes in a greased casserole dish and pour 1/3 of the sauce over them. Spread the sauerkraut on top and place the remaining potatoes in flakes on the edge of the dish. Place fish slices on top of the sauerkraut and pour the rest of the sauce over them. Bake in the preheated oven (electric cooker: 200 °C/ gas: level 3) for 25-30 minutes. Sprinkle with remaining dill and serve garnished