Smashburger Recipe

Portion beef

Divide the ground brisket into 4 equal portions (about 4 oz / 110 g each). Gently form each portion into a loose ball — do not overwork or compact the meat.

Slice onion

Peel and thinly slice the yellow onion into rings or half-rings. Separate into single layers and measure about 1 cup total.

Mix mayo and mustard in a small bowl; set aside for assembly.

Heat a skillet or griddle over medium heat. Add 1 tablespoon unsalted butter and 1/2 teaspoon neutral oil. Add the sliced onions and a pinch of salt. Cook, stirring frequently, until softened and lightly browned, about 8–10 minutes. Reduce heat if onions start to darken too quickly. Keep warm once done.

Preheat a cast-iron skillet or flat griddle over high heat until very hot (you should see faint wisps of smoke). Brush the cooking surface with the remaining 1 1/2 tablespoons neutral oil.

Place two beef balls on the hot surface spaced apart. Working quickly, press each ball down firmly with a heavy spatula or smash tool to form a thin patty about 1/4 inch thick. Hold pressure for 10–15 seconds to maintain shape and promote crust formation.

Season the exposed top of each patty with a light pinch (about 1/8 tsp) kosher salt and a grind of black pepper immediately after smashing.

Cook the patties undisturbed for 2–2 1/2 minutes, until the edges are deeply browned and crisp. Use a metal spatula to scrape and flip each patty carefully.

After flipping, immediately place one slice of American cheese on each patty. Cook another 30–45 seconds to melt the cheese and finish cooking through (total cook time per side will yield medium; cook a little longer if you prefer well done).

While patties cook, split buns and butter the cut sides with about 1/2 tablespoon butter per two buns. Toast the buns, cut-side down, on the skillet or griddle until golden and fragrant, about 30–60 seconds.

Spread the mayo-mustard mixture on the bottom buns. Place a cheese-topped patty on each bottom bun (for a double-style smashburger use two patties per bun and two cheese slices). Top the patty with a generous spoonful of grilled onions and pickles if using. Finish with the top bun.

Serve immediately while hot to preserve the crispy edges and melted cheese.