Divide the ground beef into 4 equal portions and shape into 3/4-inch thick patties. Make a slight indentation in the center of each patty to prevent puffing during cooking. Season both sides with salt and pepper.
Preheat a grill or cast-iron skillet over medium-high heat. Cook the patties for 4 minutes on the first side, then flip and cook for 3-4 minutes for medium doneness. During the last minute, place a slice of cheese on each patty and cover to melt.
Toast the hamburger buns on the grill or in a toaster until lightly golden.
Assemble the burgers: place lettuce on the bottom bun, then the patty with cheese, followed by tomato, onion, and pickle. Spread ketchup and mustard on the top bun and close the burger.
Serve immediately with your favorite sides.
Tips
For best results, avoid overworking the meat when forming patties to keep them tender.
Let the patties rest for a few minutes after cooking to redistribute juices.
Customize with additional toppings like bacon, avocado, or sautéed mushrooms.