Add ground beef, onion, garlic, salt and pepper to a skillet over medium high heat. Cook until beef is browned and onion is softened. Add tomato sauce and water. Stir in rice and bring to a boil. Turn down heat to low and cover. Simmer for 20 minutes.
Place 1/2 cabbage in a 9×13 baking dish. Cover with 1/2 rice mixture. Repeat layers. Cover with aluminum foil and bake for 1 hour. Serve with sour cream.