Cook (whole) cabbage in boiling salted water for about 30 minutes. When cabbage is tender, take out of water, let cool. When cooled, pull leaves of cabbage off. Set aside.
Cook boil in bag rice, drain
Chop onion, Mix hamburger, onion, rice and whole tomatoes together, Pour tomatoe juice from whole tomatoes in bottom of casserole dish, Spoon hamburger mixture into cabbage leaves, fold cabbage leaves around mixture, place in casserole dish.
Cook 20 to 30 minutes @ 350 degrees, long enough to cook hamburger.