Smash Recipe

In a small bowl combine mayonnaise, ketchup, yellow mustard, pickle relish, Worcestershire sauce, garlic powder, onion powder, and salt. Whisk until smooth. Taste and adjust seasoning. Refrigerate while preparing burger; sauce can be made up to 24 hours ahead.

Shred the lettuce and place in a bowl. Slice the tomato into 1/4-inch thick rounds and season lightly with a pinch of salt if desired. Thinly slice red onion, if using.

Split the buns and lightly butter the cut sides. Set aside.

Portion and season

Divide the ground beef into 4 portions (approximately 4 oz each). Lightly shape into loose balls — do not pack. Season the top of each ball with a little salt and pepper.

Heat griddle or skillet

Place a cast-iron skillet or flat griddle over medium-high heat. Add 1 tablespoon vegetable oil and let it heat until shimmering and just starting to smoke (about 1–2 minutes).

Smash and sear

Place one beef ball on the hot surface. Using a sturdy spatula (or a second spatula) and a piece of parchment or a heavy press, press the ball down firmly to about 1/4 inch thickness. Hold for 8–12 seconds to maintain the very thin patty, then remove the press. Repeat with remaining balls, leaving space between patties. Cook undisturbed for 2–3 minutes until edges brown and crispy.

Flip and cheese

Flip each patty and immediately place one slice of American and one slice of Swiss cheese on top of each patty. Cook another 30–60 seconds, until cheese is melted and patties are cooked through but still juicy. If needed, cover with a lid for 20–30 seconds to help melt the cheese.

While finishing the last patties, place the buttered bun halves butter-side down on the griddle or skillet and toast until golden, about 30–60 seconds.

Spread about 1 to 1.5 tablespoons of burger sauce on both the top and bottom buns (adjust to taste).

Place a cheese-topped patty on the bottom bun. Add a thin layer of shredded lettuce, a tomato slice, and a few rings of red onion if using. Top with the second patty (if using two patties per sandwich) or place the top bun directly on the single patty.

Serve immediately while hot. Provide extra burger sauce on the side if desired.