Coarsely chop the spinach and onions and sauté in the margarine. Sweat the flour in the leftover bacon cubes and gradually add the broth or water. Let four fifths of the spinach cook in it. Puree the soup removed from the fire and season with nutmeg and salt. Add the remaining finely chopped spinach and sprinkle grated cheese or roasted breadcrumbs on each plate of soup.