Kill Me Smash Burger Recipe

Prepare and cook aromatics

Heat a large skillet over medium heat. Add butter and olive oil. Once butter melts and oil shimmers, add the sliced onions and a pinch of salt. Cook, stirring occasionally, for about 8–10 minutes until softened and beginning to brown.

Add mushrooms and season

Add the sliced shiitake to the pan with the onions. Continue to cook over medium-low heat, stirring every few minutes, until onions are deeply golden and mushrooms are tender, about 8–10 more minutes. Sprinkle the brown sugar, balsamic vinegar, 1/4 tsp salt and 1/8 tsp black pepper. Stir and cook another 1–2 minutes to meld flavors. Remove from heat and keep warm.

In a small bowl combine 1/2 cup mayonnaise, 2 tablespoons sour cream, finely chopped scallions, grated garlic, lemon juice, 1/4 tsp kosher salt and 1/8 tsp black pepper. Stir until smooth and taste; adjust salt or lemon as needed. Refrigerate until assembly.

Portion the beef

Divide the 1 lb of ground beef into four loose 4-oz (about 113 g) portions and gently shape into loose balls—do not overwork.

Preheat griddle or skillet

Heat a cast-iron skillet or flat griddle over high heat until very hot. Add 1–2 tablespoons neutral oil and spread to coat.

Smash and sear

Place two beef balls on the hot surface (work in batches). Using a sturdy spatula or a burger press lined with parchment, smash each ball flat to about 1/4-inch thickness. Season the exposed top with a light pinch of salt and pepper. Cook without moving for 2–2.5 minutes until deeply browned and edges are lacy.

Flip, cheese, and finish

Flip each patty, immediately top with a slice of pepper jack cheese, and cook another 45–60 seconds until cheese is melted and the patty is cooked through. Remove to a plate and tent loosely with foil; repeat with remaining patties.

Toast buns

Lightly butter or oil the cut sides of the buns. Toast them on the griddle or in a skillet until golden, about 30–60 seconds, and set aside.

Build the burger

Spread 1–2 tablespoons scallion aioli on the bottom bun. Place one or two smash patties (depending on desired stack height) with melted pepper jack on the bun. Spoon a generous portion (about 2–3 tablespoons) of the caramelized onion and shiitake mixture over the cheese. Add house pickles to taste (about 2–3 slices or 1–2 tablespoons). Finish with a light smear of aioli on the top bun and close.

Serve with taro chips

Plate the burger alongside 2 cups taro chips. If chips are homemade, season immediately after frying with a pinch of salt. Serve hot.