In a large mixer bowl, cream sour cream and margarine. Beat in egg, lemon peel and juice until well combined. Combine next 5 ingredients, blend into creamed mixture only until ingredients are moistened (30-45 seconds). Line muffin pan with paper baking cups. Spoon dough evenly into cups. Bake in a preheated 400 degree oven until lightly browned and muffins test done with wooden pick (18-20 minutes). Let stand on wire rack 5 minutes, remove muffins from pan. Serve warm.