Heat a large Dutch oven over medium heat. Add beef; cook until browned, stirring to crumble. Remove beef with a slotted spoon, leaving drippings in pan.
Cook onion and next 3 ingredients in pan over medium heat 10 minutes; stir frequently. Add beef broth and next 5 ingredients. Bring to a boil; cover, reduce heat, and simmer 15 minutes.
Stir in zucchini and pasta; bring to a simmer over medium heat. Cook, uncovered, 15 to 20 minutes or until pasta is tender. Return beef to pan; cook 5 minutes or until thoroughly heated.