Carefully remove the core of the cabbage while keeping the leaves intact.

Submerge the cabbage in boiling water and cook for 5-7 minutes until the outer leaves soften.

Remove the cabbage, drain, and allow it to cool slightly.

Gently peel away the outer layers, setting aside around 10-12 large leaves for stuffing.

In a large saucepan, combine diced tomatoes, tomato paste, minced garlic, oregano, thyme, brown sugar, and salt.

Cook for about 15-20 minutes, allowing the sauce to thicken slightly. Set aside.

In a skillet, heat vegetable oil over medium heat.

Begin by adding the diced onion to the pan and cook over medium heat until it becomes soft and translucent, which should take around 4 to 5 minutes.

Next, incorporate the ground beef, using a wooden spoon to crumble it as it cooks.

Continue cooking until the meat is browned and thoroughly cooked through.

Once done, take the pan off the heat and carefully drain off any excess fat.

In a large bowl, combine the cooked ground beef, sautéed onions, cooked rice, beaten egg, salt, and pepper. Mix well to create the filling.

Take each cabbage leaf and place a generous spoonful of the filling in the center.

Fold the sides of the leaf over the filling, then roll tightly to form a neat package.

Preheat your oven to 350°F (175°C).

In a deep baking dish, spread a thin layer of the prepared tomato sauce.

Arrange the cabbage rolls in the dish with the seam side facing downward. Drizzle the leftover sauce generously over them, ensuring they are well-coated.

In a small bowl, mix 1 cup of water with the cornstarch until smooth. Pour this over the cabbage rolls.

Cover the dish with foil and bake for 1 hour.

After an hour, remove the foil, sprinkle the shredded Parmesan cheese on top, and bake uncovered for an additional 15-20 minutes, or until the cheese is golden and bubbly.

Once the stuffed cabbage is done, garnish with fresh thyme and oregano leaves if desired.

Serve hot, alongside crusty bread or a side salad.