Stuffed Cabbage with Beef and Rice

INGREDIENTS

• Coarse salt and ground pepper
• 1/2 large head green cabbage (1 1/2 pounds), cored
• 1 tablespoon olive oil
• 1 large yellow onion, diced small
• 2 garlic cloves, minced
• 2 cups crushed tomatoes (from a 28-ounce can)
• 1 tablespoon sugar
• 1 tablespoon cider vinegar
• 3/4 cup cooked long-grain white rice
• 1/2 pound ground beef chuck
• 1 large egg, lightly beaten