In medium saucepan cook onion and carrot in butter or margarine till tender but not brown.
Stir in water, sugar, bouillon granules, and salt; heat and stir till bouillon granules are dissolved.
Add shredded lettuce and water chestnuts.
Cover and simmer over low heat for 5 to 8 minutes.
Do not overcook.
Drain; transfer to serving dish and top with parsley.
Add toasted slivered almonds, if desired.