Combine tomato sauce, onions, cumin, pepper, Worcestershire, molasses, and Italian seasoning in 4-cup glass measure.
Cook on HI, 3 to 4 minutes, or until mixture boils.
Arrange ribs in 3-quart microproof casse-role.
Cover with hot broth.
Add more broth to cover, if needed.
Cover with casserole lid and cook on HI, 15 minutes.
Baste with sauce.
Cover and cook on 50, 15 to 20 minutes, or until tender.