Perfect Smash Burgers
Paper-thin crispy-edged patties stacked with American cheese, caramelized onions and special sauce.
About This Recipe
The smash burger technique, popularized by Shake Shack and In-N-Out, creates a patty with maximum surface area touching the flat-top, generating Maillard reaction on every inch. The result is a burger with more crust, more flavour and juicier interior than any traditionally shaped patty.
Ingredients
Serves 4
- 600 gbeef mince 80/20(DO NOT use lean mince)
- 8 slicesAmerican cheese (processed)(for the iconic melt)
- 4brioche or potato buns(toasted)
- 2white onions(thinly sliced into rings)
- 4 tbspmayonnaise
- 2 tbspAmerican yellow mustard
- 2 tbspketchup
- 1 tspsweet pickle relish
- 1 tspwhite wine vinegar
- salt and white pepper
- shredded iceberg lettuce
- sliced pickles
Instructions
- 1
Make the special sauce
Mix mayo, mustard, ketchup, relish, vinegar and a pinch of white pepper. Refrigerate.
- 2
Portion the beef
Divide beef into 8 loose balls of ~75g each. Don't compact or season yet — the beef should be cold and loose.
- 3
Prep the onions
Sweat onion rings in a pan with butter over medium-low heat for 15–20 minutes until deeply golden and sweet. Set aside.
- 4
Get the griddle nuclear hot
Heat a cast-iron flat-top or large skillet over MAXIMUM heat for 5 minutes. No oil needed for 80/20 beef.
The griddle must be as hot as possible — the smash creates massive heat exposure that drives the Maillard reaction.
- 5
Smash and season
Place 2 beef balls on the griddle. Immediately press down firmly with a heavy spatula or burger press, flattening to 2–3mm thin. Season with salt and white pepper. Cook 2 minutes WITHOUT moving.
- 6
Scrape, flip and cheese
Scrape the patty off the griddle with a sharp, thin spatula (the crust will stick — this is flavour). Flip. Immediately place 1 slice of American cheese on each patty. Cook 60 seconds more.
- 7
Steam the cheese (optional)
For an extra-melty result, place a metal bowl or lid over the patties with a splash of water to create steam for 30 seconds.
- 8
Build the burger
Toast buns in the beef fat. Spread special sauce on both halves. Bottom: lettuce, 2 stacked patties (double smash!), caramelized onions, pickles. Top bun.
Pro Tips
- →
80/20 beef is mandatory — leaner beef creates dry, flavourless burgers.
- →
Never season before smashing — salt draws out moisture.
- →
American processed cheese melts better than any 'real' cheese for this style of burger.
- →
The scraping step is essential — the fond sticking to the pan = the crust. Get every bit.
Variations
- •
Oklahoma onion smash: place onions on top of the beef before smashing — they caramelize directly into the patty.
- •
Patty melt: swap buns for rye bread, add Swiss cheese, grill like a sandwich.
Storage
Smash burgers are best eaten immediately. The patties can be cooked ahead and reheated on a hot skillet.
History & Origin
The flat-top smash technique has roots in American diner cooking going back decades, but was popularized by the chain Steak 'n Shake (founded 1934) and modern chains in the 2010s social media era.
Frequently Asked Questions
What if I don't have a cast-iron griddle?
Any heavy, flat pan will work. Carbon steel or stainless steel give good results. Non-stick pans cannot reach the necessary temperature — avoid them.
Nutrition Facts
Per serving (450g) · 4 servings total
Time Summary
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