In a large shallow dish, combine flour and 1/2 teaspoon pepper. Add beef, a few pieces at a time, and turn to coat. Shake off excess., In a Dutch oven, brown beef in 2 tablespoon oil; drain. Remove and set aside. In the same pan, saute the zucchini, onion, celery and carrots in remaining oil until tender. Add the garlic, oregano, basil and marjoram; cook 1 minute longer., Add wine, stirring to loosen browned bits from pan. Return beef to pan; add the tomatoes, broth, sugar and remaining pepper. Bring to a boil. Reduce heat; cover and simmer until beef is tender, 1-1/2 hours. Add tortellini and spinach. Return to a boil. Cook, uncovered, until tortellini are tender, 7-9 minutes.