Cream Of Broccoli Soup

Place broccoli in large bowl and cover with cold water. Add juice of 1 lemon and let stand 1 hour. Drain a chop broccoli. Heat butter in large saucepan over medium heat. Add onion and cook 3 minutes, partly covered. Add chopped broccoli and season well. Partly cover and continue cooking 7 minutes. Stir during cooking process. Mix in flour until well incorporated. Cook 3 minutes, uncovered over medium heat. Add remaining ingredients and mix well. Cook soup, partly covered, 30 minutes over low heat. Use food mill or blender to puree soup. Correct seasoning and serve