• Assemble all ingredients and equipment before starting.

For the tomato sauce

• Melt the butter in a large pot over medium heat. Add the chopped onion and cook until it becomes soft and translucent, about 4 to 5 minutes.
• Stir in the minced garlic and cook briefly, about 30 seconds, then add the crushed tomatoes and tomato sauce. Season with salt and pepper.
• Mix in the brown sugar and red wine vinegar. Bring the sauce to a gentle simmer and let it cook, stirring occasionally, for 10 to 15 minutes to blend flavors.

For the cabbage rolls

• While the sauce simmers, fill a large pot with water and bring it to a boil.
• Submerge the whole head of cabbage in the boiling water for 3 to 5 minutes, until the outer leaves soften and become pliable. Remove and peel away about 12 large leaves.
• Trim each leaf by cutting a V-shaped wedge from the thick stem area so the leaf can be rolled more easily.
• In a large bowl combine the ground beef, cooked rice, chopped onion, minced garlic, 2 tablespoons of the chopped parsley, egg, salt and pepper. Add 1/2 cup of the warm tomato sauce and mix until evenly combined.
• Portion roughly 1/3 cup of the meat mixture, shape it into a short log, place it across the base of a cabbage leaf and roll the leaf around the filling, tucking in the sides. Repeat until all rolls are formed.
• Preheat the oven to 350°F (175°C). Coat a 9x13-inch baking dish with cooking spray and spread half of the tomato sauce across the bottom.
• Arrange the cabbage rolls seam-side down in the prepared dish. Spoon the remaining sauce over the top to cover the rolls.
• Cover the dish tightly with foil and bake for 60 to 90 minutes, until the cabbage is tender and the filling is cooked through.
• Remove from the oven, sprinkle with the remaining parsley, and serve warm.