1 teaspoon garlic salt, divided
1/2 teaspoon pepper, divided
8 thin slices Swiss cheese
4 thin sandwich pickle slices
1) Prepare grill for medium heat. Place a large cast-iron skillet on grill grates.
2) In a large bowl, combine beef, pork, lemon juice, 1/2 teaspoon garlic salt and 1/4 teaspoon pepper, mixing lightly but thoroughly. Shape into four 1/2-in.-thick patties.
3) Grill burgers, covered, over medium heat until a thermometer reads 160°, 5-7 minutes on each side.
4) Combine mayonnaise, mustard, remaining 1/2 teaspoon garlic salt and 1/4 teaspoon pepper; spread over cut sides of buns. Place burgers on bun bottoms; top with Swiss cheese, ham, pickles and bun tops.
5) Using oven mitts, carefully place preheated skillet on sandwiches. Grill sandwiches, covered, until buns are browned and cheese is melted, 5-8 minutes.