Combine flour, salt, and pepper; dredge chuck roast in flour mixture. Brown the roast on all sides in hot oil in a large Dutch oven.
Slice olives, reserving liquid. Place sliced olives and onion on top of roast. Combine tomato puree, water, and reserved olive liquid; pour over roast. Cover and simmer 2 1/2 hours or until meat is tender.
Remove roast to a warm serving platter; spoon pan drippings over roast. Serve with hot cooked rice and hot sauce.