In a medium bowl, combine the beef, egg, bread crumbs, cheese, basil and onion. Shape mixture into 3/4 inch balls and set aside. In a large stockpot heat chicken broth to boiling; stir in the spinach, pasta, carrot and meatballs. Return to boil; reduce heat to medium. Cook, stirring frequently, at a slow boil for 10 minutes or until pasta is al dente. Serve hot with Parmesan cheese sprinkled on top.