Cut approx ¼" off the bottom of the head and place the whole head of cabbage in boiling water. Boil about 2 minutes. Peel off the softened leaves. Place remaining head back in the boiling water and repeat until all of the leaves are removed. Remove any tough stems from cooked leaves
Cook rice according to package directions but reduce cooking time by 5 minutes so the rice is slightly underdone. Set aside.
Cook pork (or turkey), beef, onions, garlic, & seasonings in a pan until no pink remains. Drain any fat. Add in rice, diced tomatoes, & ⅓ cup of tomato sauce. Stir in egg
Spread a very thin layer of the tomato sauce mixture in a 9x13 pan
Remove or thin any thick stem on cabbage leaves. Lay the cabbage leaf flat and add ¼ to ⅓ cup filling to the center of the leaf. Fold in the sides and roll the cabbage up. Place seam side down in the pan. (See note for small leaves). Repeat with remaining cabbage
Pour sauce over the cabbage and cover tightly with foil. Bake for 75-90 minutes. Let cool for 15 minutes before serving