In a mixing bowl, combine ground beef, salt, and black pepper. Mix gently to combine.

Divide the mixture into 4 equal portions and shape them into patties.

Preheat the grill to medium-high heat.

Place the patties on the grill and cook for about 4-5 minutes on each side, or until they reach an internal temperature of 160°F (71°C).

If using cheese, place a slice on each patty during the last minute of cooking to melt.

Toast the hamburger buns on the grill until golden brown.

Place each patty on the bottom half of a bun. Top with lettuce, tomato, onion, pickles, ketchup, and mustard.

Cover with the top half of the bun and serve immediately.