Peel and finely chop the onion, heat the clarified butter and steam the onion until translucent. Squeeze the fresh sauerkraut well, add to the onions and cook for about 5 minutes. Season to taste with salt, pepper and caraway seeds. Brush the ham slices with the mustard, cover with sauerkraut and roll up. Preheat the oven to 200 degrees. Butter a flat baking dish and insert the rolls. Cover with the cheese slices and pour on the beer. Baked golden yellow for about 15 minutes. Then sprinkle with paprika powder and serve. This goes well with mashed potatoes.