Brown your choice of ground beef or turkey in a large skillet over medium heat for 5-7 minutes until fully cooked. Drain excess fat and set aside.

In the same skillet, sauté chopped onion and minced garlic over medium heat for 2-3 minutes until fragrant. Mix with the browned meat.

Combine the meat and sautéed onions with uncooked rice, crushed tomatoes, tomato sauce, Worcestershire sauce, oregano, basil, salt, and pepper in a large mixing bowl.

Layer half of the chopped cabbage in the bottom of the slow cooker. Add half of the meat mixture, then repeat with remaining cabbage and meat.

Cover and slow cook on Low for 6-8 hours or High for 3-4 hours until the cabbage is tender and rice is cooked.

Fluff the casserole with a fork, optionally adding shredded cheese on top before serving for a melty finish.