Wash the potatoes. Cook in salted water with some caraway seeds for about 10 minutes. Then let it cool down a little. In the meantime wash and chop the parsley. Peel onions, cut into rings and turn them in flour.
Just before serving, bake in hot frying fat until crispy and turn in chopped parsley. Wash apples, quarter them, remove seeds and cut into small pieces. Fry them in hot fat. Season with sugar, cinnamon stick, star anise and vanilla pulp.
Deglaze with white wine and Calvados. Cook for about 5 minutes, crush it slightly with a skimmer and season again. Peel potatoes, grate coarsely. Stir in egg yolk. Season to taste with salt, pepper and nutmeg.
Form 16 small Rösti from it. Cover 8 pieces with 1 slice of black pudding each. Place the rest of the Rösti on top and press on. Fry in hot oil for about 3 minutes on each side. Serve with spiced apples and baked onion rings.
Garnish as desired with parsley and apple slice.