Place the ground beef in a bowl. Add kosher salt, black pepper, and Worcestershire sauce. Gently combine with your hands or a fork until just mixed — do not overwork. Divide the meat into 4 equal portions (about 4 oz each for a thinner Frontier-style patty or 6-8 oz for thicker patties).

Form patties

Shape each portion into a loose ball, then flatten into patties about 3/4" (2 cm) thick with a slight depression in the center to prevent doming while cooking. Press a small indentation with your thumb in the middle of each patty.

Chill briefly (optional)

If time allows, refrigerate formed patties 15-30 minutes to help them hold together during cooking. If using very cold beef, you can cook immediately.

Buns & Sauce

Make sauce

In a small bowl combine mayonnaise, Dijon mustard, ketchup and hot sauce (if using). Taste and adjust seasoning. Set the sauce in the refrigerator until ready to assemble.

Prepare buns

Split the buns and butter the cut sides with the 2 tbs of unsalted butter reserved for toasting.

Cheese & Toppings

Prepare vegetables

Thinly slice the red onion into rings (about 1/8" thick). Slice the tomato into 4 even slices. Wash and pat dry the lettuce leaves and set aside. Have pickles and cheese slices ready on a plate.

Cooking & Finish

Preheat pan or grill

Heat a cast-iron skillet or heavy griddle over medium-high heat until very hot, about 4-5 minutes. Add 1 tbs vegetable oil and spread to coat the surface. If grilling, oil the grates well.

Cook patties

Place patties on the hot surface leaving space between them. Cook undisturbed for 3-4 minutes to develop a brown crust. Flip and immediately add 1/2 tbs softened butter on top of each patty (optional) to baste. Cook the second side for 2-4 minutes depending on thickness and desired doneness (aim for 160°F/71°C for well-done).

Add cheese

About 1 minute before the patties are done, place a slice of cheddar (and a slice of smoked gouda if using) on each patty. Cover the pan briefly with a lid or tent with foil to melt the cheese, about 30-60 seconds.

Toast buns

While cheese melts, toast the buttered cut sides of the buns in a separate skillet or on the grill for 1-2 minutes until golden and crisp. Keep warm.

Assemble burgers

Spread about 1 tbs of the prepared sauce on the bottom half of each bun. Place a lettuce leaf on each bottom bun, then the cheese-topped patty, then tomato slice, red onion rings and 2 pickles per burger. Spread a little sauce on the top bun and close the burger.

Serve

Serve immediately while hot with fries or a side salad. Provide extra sauce on the side if desired.