1) Make the sauce
In a small bowl, stir together the mayo, ketchup, mustard, chopped pickles, and pickle brine if using. Season with a pinch of salt and pepper. Set aside.

2) Form the patties
Divide the beef into 4 equal portions (about 6 ounces each). Gently form into patties about 3/4-inch thick. Press a small dimple in the center of each patty with your thumb to help it cook evenly.
Season both sides with the salt, pepper, and garlic powder if using.

3) Sear the burgers
Heat a large skillet over medium-high heat until very hot, about 2 to 4 minutes. You are looking for the pan to be properly preheated and the oil to shimmer and just start to smoke lightly.
Add the oil and swirl to coat.
Add the patties and cook without moving them for 3 to 4 minutes, until a deep brown crust forms and the edges look browned. Flip once and cook another 2 to 4 minutes, depending on thickness and desired doneness.
Timing varies a lot by pan and stove, so use the clock as a guide and the burger as the truth. If you have a thermometer, aim for 160°F for fully cooked ground beef.
Note: If your skillet is crowded, cook in batches so the patties sear instead of steaming. And if things are smoking aggressively, turn the heat down a notch and run your vent.

4) Melt the cheese
Turn heat to medium-low. Top each patty with a slice of cheese. Add a splash of water to the pan (about 1 tablespoon) and cover for 30 to 60 seconds to melt the cheese fast. Use a skillet lid if you have one, or cover with a sheet pan or a loose tent of foil.

5) Rest, then toast the buns
Move patties to a plate and let them rest while you toast the buns, about 2 minutes. This keeps them juicier and gives you time to deal with the pan.
Carefully pour off excess beef fat (leave a thin film for flavor) or wipe the skillet with paper towels using tongs. Then add the butter and toast the cut sides of the buns until golden, about 1 to 2 minutes. This step is small but it changes everything.

6) Build and eat
Spread sauce on the buns, add the cheesy patty, and pile on your toppings. Serve immediately while the edges are still crisp and the bun is still warm.