Broccoli Soup

1 (10 ounce) package frozen chopped broccoli
1/2 cup chopped onion
1 1/2 tablespoons butter
1 1/2 cups milk
1 cup water
1 can cream of chicken soup

Cook broccoli (omit salt) until tender; drain. Place everything in large pot over medium heat until slightly boiling. Stir often.