Divide the ground beef into four equal portions and gently shape each into a patty about 3/4 inch thick, avoiding overworking the meat for tender burgers.
Preheat your grill or skillet over medium-high heat until hot, and optionally toast the buns until golden on the cut sides.
Season each beef patty generously with salt and pepper on both sides for flavor.
Place the patties onto the hot grill or skillet, hearing a satisfying sizzle as they make contact, and cook for about 3-4 minutes per side until nicely browned and slightly crispy on the edges.
Lay a slice of cheese on each patty during the last minute of cooking to allow it to melt beautifully.
While the patties finish cooking, sauté the sliced onions in a little oil until they soften and develop a light caramel color, about 5 minutes.
Assemble each burger by spreading the special sauce on the bottom bun, then layering with pickles, a beef patty with melted cheese, caramelized onions, and the top bun.
Serve the cheeseburgers immediately, with extra toppings or side dishes as desired, enjoying the juicy, flavorful patty with the crispy edges and melty cheese.
