Preheat the oven to 350 degrees F. Lightly grease a casserole dish with at least a 3-quart capacity. A Dutch oven or wide, ovenproof pot would work well, too. (I have also used a 9×13 Pyrex dish. In this case, lightly grease a piece of foil prior to covering.)
In a large bowl, combine the beef, sausage, onion, rice, parsley, eggs, 1 teaspoon of salt and the pepper. (If you prepared the rice with no salt, add the additional ½ teaspoon of salt now.) To prevent the meat from becoming tough, avoid over mixing.
Line the bottom of the casserole with half of the chopped cabbage. Sprinkle half of the meat mixture over the cabbage. Top with the remaining cabbage, followed by the rest of the meat mixture.
Combine the tomato sauce and the beef broth. Pour the tomato mixture over the meat and cabbage. Place the lid on top of the casserole dish and bake for one hour. After an hour, remove from the oven, and spread the sour cream over the top. Return to the oven and bake, uncovered, for additional 25-30 minutes. Allow to rest 5-10 minutes before serving.