Finely dice the onions and fry in butter. Peel the carrots and celery, dice finely, add to the onions and add the vegetable stock. Bring the soup to a boil and simmer for about 20 minutes. When the vegetables are soft, puree everything with the magic wand, pour on the cream or crème fraîche and season with pepper, salt and nutmeg.
Clean the chanterelles and fry them well in butter, season with salt and pepper.
To serve, put the soup in cups or plates, put about 1 tablespoon of the fried chanterelles in the center and sprinkle with a little cress.