Clean the spring onions and carrots and cut into very small cubes.
Toast the semolina in the butter until golden. Add the vegetables, sauté briefly and fill up with the stock. Cook gently for 5 - 10 minutes while stirring. Whisk the crème fraîche with the egg yolk and stir into the soup. Don`t let it boil anymore. Season with salt, pepper and nutmeg. Mix in the chopped parsley.