Shape your ground beef into 6 patties. Make in indention in the middle of each patty. This helps the patty to end up cooking nice and flat, rather than getting all puffy in the center.
Liberally season both sides of the patty with garlic salt and pepper. If the garlic salt scared you, just go with regular salt.
Grill the patties until fully cooked.
Add the slices of cheese to the patties and allow to melt. Remove patties from the grill.
Assemble burgers on the buns and top with the remaining ingredients.