Garlic Parmesan Cheeseburger Bombs INGREDIENTS: For the Cheeseburger Filling: 1 lb ground beef 1/2 onion, finely chopped 1 cup shredded cheese (cheddar or mozzarella) Salt and pepper to taste 1 tablespoon Worcestershire sauce 1 tablespoon ketchup 1 tablespoon mustard For the Garlic Parmesan Butter: