Serrano Smash Burger Recipe

Prep

Thinly slice the yellow onion into half-moons. Thinly slice the serrano peppers and jalapeño into rounds; remove seeds from peppers for less heat if desired.

Char the peppers

Heat a dry cast-iron skillet or griddle over high heat until smoking. Add serrano and jalapeño slices in a single layer and blister, about 1–2 minutes per side, until blackened in spots. Transfer to a plate and set aside.

Caramelize onions with bourbon

Reduce heat to medium. Add 1 tbsp butter and 1 tsp olive oil to the same pan. Add the sliced onions and a pinch of salt. Cook, stirring occasionally, until soft and beginning to brown, 10–12 minutes. Sprinkle 1 tsp sugar over the onions, stir, then add 1 tbsp bourbon and 1/2 tsp apple cider vinegar. Continue cooking another 3–5 minutes until deeply caramelized and glossy. Remove from pan and keep warm.

Portion the beef

Divide the 1 lb ground beef into four equal balls (~4 oz each). Do not overwork the meat; loosely form into round balls.

Preheat cooking surface

Heat a heavy cast-iron skillet or griddle over high heat until very hot. Add 1 tbsp vegetable oil and spread.

Smash the patties

Place two beef balls on the hot surface (work in two batches). Immediately press each ball flat with a sturdy spatula or a weighted burger press to about 1/4-inch thickness. Season the exposed side generously with ~1/2 tsp salt and a light sprinkle of black pepper per two patties (use remaining salt/pepper for the next batch). Cook without moving for 2–3 minutes, until deep brown and crisp around the edges.

Flip and top

Flip the patties. Quickly place one slice of pepper jack onto each patty, then add some blistered serrano/jalapeño rounds and a spoonful of the bourbon caramelized onions on top of the cheese. Cook another 30–60 seconds until cheese melts and patties are cooked through (smash patties cook fast).

Toast buns

While finishing the second batch, butter the cut sides of the buns. Toast buttered sides on the hot skillet until golden, about 30–45 seconds.

Assemble burgers

Spread about 1 tbsp mayonnaise on each bun bottom. Place 2 patties stacked on each bun bottom (for a double), ensuring cheese, peppers, and onions are between layers. Add optional pickles or lettuce if using. Cap with bun tops.