Drain 1 cup ripe olives, reserving liquid. Chop ripe olives finely. Mix with parsley, cheese, 2 teaspoons chili powder, salt and garlic.
Make about 15 slits in roast, and force ripe-olive mixture down into slits.
Brown roast slowly on all sides in an oiled skillet or Dutch oven. Drain off and discard fat.
Add onion to meat and brown lightly. Mix tomato sauce with 1/2 cup liquid reserved from olives and remaining teaspoon of chili powder and pour over roast. Heat to boiling, reduce to low heat and cover pan. Simmer about 2 hours or until meat is tender, basting once or twice.
Pare and cut carrots into thick diagonal slices. Wash zucchini and cut into halves. Add carrots to meat 30 minutes before meat is done. Cook 15 minutes, then add zucchini and remaining olives and cook 15 minutes longer.
When meat and vegetables are tender, remove to heated serving dish. Skim fat from remaining pan liquid. Mix flour with 2 tablespoons cold water. Add a little of the hot liquid, then combine with remaining liquid in pan. Cook, stirring until mixture boils and thickens. Serve sauce over meat and vegetables.