1Cook rice in water as directed on package. Meanwhile, in 12-inch skillet, cook beef and onion over medium-high heat 5 to 7 minutes, stirring occasionally, until beef is thoroughly cooked and onion is tender; drain.
2Add gingerroot, curry powder, cumin and salt to skillet; cook 1 minute, stirring occasionally. Stir in sweet potato, tomatoes and broth. Heat to boiling; reduce heat. Cover; simmer 10 minutes or until potato is almost tender. Stir in zucchini. Cover; cook 5 to 10 minutes longer or until potato and zucchini are just tender.
3Serve beef mixture over rice. Top each serving with about 1 tablespoon yogurt.