Fill a large pot with water and bring it to a boil. Carefully remove the core from the cabbage with a sharp knife, then place the entire head of cabbage in the boiling water. Blanch for about 5-7 minutes, or until the leaves are pliable. Remove and let cool slightly.

In a large bowl, combine the ground beef or turkey, cooked rice, chopped onion, egg, garlic powder, paprika, salt, and pepper. Mix well until all ingredients are incorporated.

Carefully peel off individual leaves from the cabbage. Place about 2-3 tablespoons of filling on the bottom edge of each leaf. Fold the sides towards the center and roll from the bottom up. Secure with a toothpick if needed.

Preheat your oven to 350°F (175°C). Spread a thin layer of tomato sauce on the bottom of a baking dish. Arrange the cabbage rolls seam-side down in the dish and pour the remaining tomato sauce over the top.

Cover the dish with foil and bake for about 45 minutes. Then remove the foil and bake for an additional 15 minutes to allow the rolls to soak in the sauce's flavor.

Once cooked, let them cool for a few minutes and serve warm, topped with fresh herbs or a spoonful of yogurt if desired.