Bring a large pot of water to a boil. Carefully remove the core from the head of cabbage and place it in the boiling water. Boil for about 5 minutes, or until the outer leaves are tender. Gently peel off the soft leaves and set aside.
In a large mixing bowl, combine ground beef or pork, cooked rice, onion, garlic, salt, black pepper, thyme, and paprika. Mix until well combined.
Preheat your oven to 350°F (175°C).
Take one cabbage leaf, place about 2-3 tablespoons of the meat mixture at the base of the leaf, and roll up tightly, folding in the sides as you go to seal the filling inside. Repeat with remaining leaves and filling.
In a large baking dish, spread a thin layer of tomato sauce on the bottom. Place the cabbage rolls seam-side down in the dish.
In a saucepan, combine the remaining tomato sauce and diced tomatoes. Stir well and pour over the cabbage rolls, ensuring they are covered.
Cover the baking dish with aluminum foil and bake in the preheated oven for 60 minutes.
After 60 minutes, remove the foil and bake for an additional 10 minutes to allow the tops to brown slightly.
Remove from the oven and let cool for a few minutes before serving.