Cut the fish into bite-sized cubes, drizzle with lemon juice and season with salt and pepper.
Remove the stalk of the cabbage. Wash the leaves and cut into fine strips. Peel and finely chop shallot.
Heat some butter in a saucepan and sauté the shallots in it. Add the savoy cabbage and a cup of water and cook covered over low heat for approx. 8 minutes. Season with salt, freshly ground pepper and grated nutmeg. Stir in the crème fraiche. Turn off the stove, place the salmon on top of the vegetables, fold in and let stand, covered, for approx. 5 minutes (the salmon really doesn`t take longer).
Wash the dill, shake dry and roughly chop. Arrange savoy cabbage with salmon on plates and serve sprinkled with dill.