Preheat the oven to 350°F. Spray a large 9x13 inch baking dish with non-stick cooking spray.

Prepare Cabbage Leaves: Bring a large pot of water to a boil. Cut and remove about 1 inch from the bottom of the head of cabbage. Place the entire head of cabbage into the pot of boiling water and boil for 4-5 minutes or until the leaves peel easily and are pliable.

Remove the boiled head of cabbage from the pot and place on a dish towel to let drain. Once cool to the touch, peel 12 cabbage leaves from the head, being careful not to tear them.

Make the Tomato Sauce: Add oil and 1 cup diced onion to a large skillet over medium heat. Cook 2-3 minutes, or until the onion has softened. Add garlic and continue cooking for another minute.

Add the tomato sauce, crushed tomatoes, Worcestershire sauce, sugar, 1 teaspoon salt and ½ teaspoon black pepper. Stir to combine. Increase heat to high and bring sauce to a boil. Once boiling, reduce heat to low and simmer, uncovered, for 10-15 minutes.

Make Meat Mixture: Add all filling ingredients to a large bowl. Mash the ingredients together using a potato masher until well combined.

Assemble the Cabbage Rolls: Place one cabbage leaf on a cutting board. Cut a V-shaped incision at the base of each leaf to remove the bottom 1-2 inches of the tough rib. Add about 3-4 tablespoons of the filling mixture into each leaf. Fold the right side of the leaf over the filling and then fold the left side over. Starting at the base, begin rolling the cabbage leaf up. Repeat the previous steps with the remaining filling and cabbage leaves.

Bake in the Oven: Pour the tomato sauce into the prepared baking dish and spread it out to completely coat the bottom. Place cabbage rolls, seam side down, in two rows of six rolls. Cover the baking dish with a piece of aluminum foil and bake in the oven for 60-75 minutes. You'll know they're done cooking when the internal temperature reaches 165℉. Let rest for 5-10 minutes before serving with a sprinkle of parsley, if desired.