Double Oklahoma Onion Smash Burgers with Homemade Burger Sauce
This one is mine, start to finish. Paper-thin onions smashed right into the beef on a ripping hot cast iron skillet, two patties under melted cheese, a quick homemade sauce, and buns toasted in the drippings. It’s so flavorful that some nights I skip the bun entirely.
The method is an Oklahoma onion burger, a Depression-era way of stretching beef with onions. The onions cook into the crust and turn sweet and caramelized, and they’re the whole point.
The ingredients matter here. I’ve tried plenty of cheeses, buns, and pickles, and the ones in this recipe are the ones I keep coming back to. Covering the pan with a splash of water to melt the cheese matters just as much, so don’t skip it. And toasting the buns in the beef fat left in the skillet is one of the biggest flavor upgrades in the whole recipe.
Bacon is great on these. It’s also a lot.

Double Oklahoma Onion Smash Burgers
Ingredients
Equipment
Method
- Make the sauce. Stir together all the burger sauce ingredients and refrigerate while you cook.
- Slice the onions as thin as you possibly can. The thinner they are, the better they melt into the burger crust.
- Divide the beef into 12 loosely packed balls, about 4 oz each. Don’t compress them.
- Heat a cast iron skillet over medium-high to high heat until very hot. No oil needed.
- For each patty, add a small pile of onions to the skillet and set a ball of beef right on top. Immediately smash it hard and thin, to about 1/4 inch, using a sturdy metal spatula, a burger press, or the bottom of a heavy pot. Season with salt and pepper.
- Cook untouched for 1 1/2 to 2 minutes, until deeply browned with crispy edges and the onions are caramelized into the beef.
- Scrape firmly underneath the patty, keeping the onions attached, and flip. Add a slice of cheese right away.
- Add a small splash of water to the pan and cover for 30 to 60 seconds, until the cheese is completely melted. Stand back, since the water will sputter in the hot pan.
- Repeat with the remaining beef, working in batches.
- Toast the buns cut-side down in the beef fat left in the skillet.
- Assemble: spread sauce on the bottom bun, stack two cheesy patties, add extra skillet onions and any toppings you like, then spread more sauce on the top bun.