INGREDIENTS: 1 1/2 pounds ground beef; 1 tablespoon Worcestershire sauce; 3/4 teaspoon garlic salt; 1 teaspoon black pepper; 4 slices American cheese; 4 hamburger buns, split.
DIRECTIONS: Combine ground beef, Worcestershire sauce, garlic salt and pepper in a large bowl. Mix well. Form 8 thin patties from the beef, each patty should be slightly larger than a slice of the cheese. Cut each slice of American cheese into 4 equal pieces and stack the pieces. Sandwich one stack of cheese between 2 ground beef patties. Tightly pinch edges together and tightly seal the cheese within the meat. Repeat with the remaining cheese patties. Preheat a cast iron or other heavy bottomed skillet over medium heat. Cook burgers until well browned, about 4 minutes. It is common for the burgers to puff up due to steam from the melting cheese. Turn the burgers and prick the top of each to allow the steam to escape. Cook until browned on the outside and no longer pink inside, about 4 minutes. Serve on the hamburger buns.