Preheat your oven to 350°F (175°C).
Bring a large pot of water to a boil. Carefully add the whole head of cabbage and cook for 2-3 minutes to soften the leaves. Remove and let cool slightly.
Heat a skillet over medium heat and add the chopped onion and garlic. Sauté until the onion becomes translucent, about 5 minutes.
In a mixing bowl, combine the ground beef, uncooked rice, sautéed onion and garlic, paprika, salt, black pepper, dried thyme, and parsley. Mix well to combine.
Carefully separate the cabbage leaves from the head and trim them if necessary to make them easier to roll.
Take one cabbage leaf and place a generous spoonful of the meat mixture at the base of the leaf. Roll it up tightly, tucking in the sides to secure the filling. Repeat this step for the remaining leaves and filling.
In a baking dish, spread a thin layer of tomato sauce and place the stuffed cabbage rolls seam-side down. Pour the remaining tomato sauce and diced tomatoes over the top, then add ½ cup of water.
Cover the baking dish with foil and bake in the preheated oven for 60 minutes. Then, remove the foil and bake for an additional 30 minutes to slightly caramelize the top.
Serve the stuffed cabbage rolls hot, garnished with additional fresh parsley if desired.