Saute the onion in 2 tablespoons butter or margarine until soft. Add the beef and rice and cook briskly for about 3 minutes, stirring. Turn into a shallow casserole, about 2-½-quart size. Shred cabbage finely and arrange over the meat mixture.

Melt the remaining 4 tablespoons butter or margarine and blend in the flour. Cook until bubbly, then remove from the heat and stir in the garlic, catsup, tomatoes, water, parsley, salt and pepper. Simmer, stirring, about 5 minutes. Pour over cabbage. Cover and bake at 350 degrees for 30 minutes.