Cook fettuccini to desired doneness as directed on pkg. Drain and keep warm. Meanwhile, melt margarine in lg. skillet or Dutch oven over Low heat. Add ham and asparagus or beans. Cook and stir for 3-4 mins. or until well heated. Stir in cream, lemon juice and lemon peel, if using. Mixture will look curdled. Cook over Low heat for 3 minutes or until mixture thickens slightly and is smooth, stirring frequently. Immediately stir in cooked fettuccine. Toss to coat with sauce. Garnish with additional lemon peel., if desired.