Why is cast iron good for cooking burgers?
There’s no doubt about it: a cast iron skillet is the best tool for making diner-style smash burgers at home.
The key to a great burger is the Maillard reaction: this is the chemical process that gives well-browned foods their delicious flavor. It’s what gives your seared steak a perfect crust, with the best umami flavor concentrated on the outside.
Smash burgers follow the same logic: if all the best flavor is concentrated on the outer crust, then maximizing the surface area will maximize the delicious Maillard flavor. That’s why we smash! For a perfectly-cooked patty with a salty, crackly, well-browned crust, a hot skillet is the closest thing to a diner flat-top — and a well-seasoned pan will clean up just as easily.
How do you make smash burgers in a cast iron skillet?
Let’s start with the skillet. You need enough space on the cooking surface smash with your spatula, so a larger skillet will work better. A Field No.10 or extra-large No.12 is your best bet, but a No.8 will do in a pinch. If you’re cooking for two, it’s easiest to use two pans.
When you’re ready to smash, it’s best to use a broad, firm, and flat spatula, cast iron grill press, or even the bottom side of a smaller No.4 Skillet. Our Cherry Slotted Turner will do the trick with firm pressure applied, but it's best to use a non-slotted tool. Pro tip: you’ll want a Leather Handle Cover to make sure you have a firm grip on the skillet in order to safely apply full force on the spatula smash, and again when it's time to flip.
How do you make thin hamburger patties?
It all starts with good ground beef: you want an 80/20 blend (that’s lean vs. fatty meat), or even as far as 70/30 to maximize flavor. To achieve a thin patty, start with a roughly 5 oz. ball of ground beef and form it into a medium-tight sphere. It needs to be loose enough to flatten out easily in the pan, but should remain in a single piece.
When you add your balled burger to the pan, apply firm downward pressure until it spreads out into a single thin patty. It’s easy to go thinner in a larger skillet: there’s more room to spread, and you can more comfortably press downward without sidewalls in the way.
Cast Iron Skillet Smash Burgers
Fatty ground beef: 80/20 is fine, 70/30 is better!
Sliced American Cheese
Bun: Martin’s Potato Roll is best, but any soft, absorbent bread will do
Onion, chopped or sliced to taste
Iceberg lettuce, sliced
Ketchup, Mayo, Mustard
Roll burger meat into 5oz balls, medium tight. You don’t want them to fall apart, but you don’t want to create a super tight sphere either. Do not salt ahead of time.
Assemble mise en place, including salt, pepper grinder, smashing tool. (Smash burgers cook fast, so toppings need to be ready ahead of time!)
Pre-heat skillet on medium-high to desired temperature of 400-500°F. No oil necessary.
Hold spatula near hot skillet, and apply a small amount of neutral cooking oil or butter. (A cold smashing tool can create sticking, so a bit of grease and heat helps.)
Place 5 oz ball of ground beef in the center of your cooking surface pan. Within about 30 seconds, Smash into as thin a layer as you can manage. (There is really no such thing as too thin here!)
Season with salt and pepper. Cook until you can see browning and caramelization around the edges, approx 2-3 minutes.
The flip: slide a thin, sharp spatula, under the smash burger, attempting to leave no Maillard behind. Flip and season again with salt and pepper. Cook for the same amount of time — this is about burger browning, and not internal temperature. The patty should be thin enough to cook quickly.
When nearly done, melt 2 slices of cheese on top. Remove from pan when cheese is melted.
Toast bun, using leftover fat in pan if desired.
Assemble the burger. Preferred sequence:
Burger + cheese
Eat immediately, repeat often.
Cast Iron Cookware that Makes Clean-up Easy
The key to reliable, use-it-every-day cast iron is seasoning: a smooth, well-seasoned skillet will clean up with just a quick wash, and produce natural non-stick performance that gets better every time you use it. Try the smooth Field Cast Iron Skillet.