Chef Will’s Famous Smash Burger Recipe

During the pandemic, when most people were obsessing over  sourdough, I spent time working with ground beef, onions and American cheese. I was inspired by the Kansas City fried onion burger, a regional classic burger that is gaining lots of popularity via George Motz (The Burger Scholar) and the burger at East Side Big Tom’s in Olympia. Our burger is a mash-up of these two magical burgers.

Serves: 4 (double burgers)


  • Flat top grill or cast iron skillet
  • Big metal spatula (for smashing)
  • Mandoline (set as thin as possible)
  • Tongs



  • 40oz ground beef (80% lean, 20% fat)
  • 2 large sweet onions (walla walla)
  • 8 slices American cheese
  • 8 Martin’s Potato Rolls (or Franz Hawaiian Buns)
  • Clarified Butter
  • Salt

Goop Sauce:

  • 265g      Mayonnaise
  • 80g        Yellow Mustard
  • 50g        Dill Pickles, finely chopped
  • 25g        Bread and Butter pickle, finely chopped


  1. Make your sauce! Mix all of the ingredients together, store for later use.
  2. Preheat your griddle or cast iron skillet over medium heat, until it reaches just under 400*F
  3. Portion your ground beef into 2.5oz balls
  4. Slice your sweet onions as thin as possible using a mandoline
  5. Pour some melted clarified on your griddle or cast iron, using a pair of tongs and a paper towel spread it evenly across the grill.
  6. Toast your buns well, darker than golden brown is ideal here. Remove and store on a tray.
  7. Place the ground beef balls on your griddle or flat top, placing each burger at least 3-4 inches apart. Season each ball with salt.
  8. Grab a handful of thinly sliced onions, place on top and around your burger.
  9. Using your stiff metal spatula, smash the heck of out each ball to make a patty (it’s rare to smash them too thin). We smash ours quite a bit, and make sure that at least 1-2” of burger will extend out past the bun. Once smashed, let them sit until some liquid begins to form on top of the patty. 1-2 minutes.
  10. Flip the beef and onion burgers and place a slice of American cheese on top of each burger.
  11. Cook for another 1-2 minutes. Remove the burgers and place onto the bottom bun. Top each burger with 1oz or so of Goop Sauce and rest the top bun on the sauced patty. Serve immediately.

Happy Grilling!

– Chef Will Preisch