Sauté 4 c. chopped leeks or onions in 2 tbs butter until soft. Add 2 quarts water or vegetable broth and simmer another 20 min. Add salt or soy sauce to taste. For a treat, ladle soup into bowls and top with grated parmesan cheese and place under broiler until the cheese starts to bubble. Variation: add cubes of peeled potatoes to the leeks and boil until tender, then blend until smooth.