Cast Iron Smash Burgers for the win! These classic, straightforward burgers are cheesy, flavorful, and irresistible.
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Anyone else love a good smash burger? They’re certainly a huge hit in our household. Oddly enough, we don’t own a grill. We have an offset smoker that we adore, and while we could technically use it as a charcoal grill, cast iron skillets work perfectly in this recipe. They’re work horses in the kitchen, heating up quickly and maintaining the heat throughout the cook. I simply love them…and these burgers!

Onto the burger:
We’re going to start by grating a yellow onion and cooking it way down…like all the way down. We want any excess water to evaporate. This onion will get mixed into the burger mixture, and man, it’ll add such a fantastic flavor.
Next, we’re going with a 50/50 blend of ground chuck and sirloin. This combo will get you not only great flavor, but it’ll also be super juicy. No dry burgers here.

Buns! A soft, buttery, perfectly toasted brioche bun is the way to go. Or a potato roll…or a sesame seed bun. There is no wrong answer here. All carbs are loved equally in this space!

Lastly we need to talk about toppings. I kept it classic; sharp cheddar cheese, mustard, ketchup, lettuce, tomato, and pickles. I do, however nix the onion, since you’re getting the kick from the cooked onion in the burger. Or…ya know…add whatever you like. You do you!

These Cast Iron Smash Burgers are (excuse my French) so damn good. And sometime, a damn good burger is all you need. Enjoy friends!

Cast Iron Smash Burgers
Equipment
Ingredients
- 1 medium yellow onion grated
- 2 tsp vegetable oil divided
- 1 lbs ground chuck 20% fat
- 1 lbs ground sirloin
- 1½ tsp salt
- ½ tsp black pepper
- 1 tsp onion powder
- 8 slices sharp cheddar cheese
- 8 brioche buns toasted
- ketchup optional
- yellow mustard optional
- lettuce washed and dried
- tomato sliced
- pickles optional
Instructions
- Heat the vegetable oil in a 12in cast iron skillet over medium heat. Once hot, add the grated onion. Cook the onion until soft, translucent and just starting to caramelize, about 2 minutes. Remove the onions from the pan and set to the side to cool.
- In a large bowl, combine the ground chuck, ground sirloin, cooked onions, salt, pepper, and onion powder. Loosely form the mixture into 8 balls. Set to the side.
- Heat the remaining vegetable oil in the skillet over medium high heat. Once hot, add 4 meat balls, evenly spaced into the skillet. Press down, using a large metal spatula, until the patty is ½ in thick. Allow the patties to cook for 2 minutes before flipping. Once flipped, top each patty with a slice of sharp cheddar cheese. Continue to cook for 2 minutes. Remove the patties from the pan and set to the side. Repeat the process with the remaining meat.
- Transfer the cooked patties to toasted buns. Serve immediately with your favorite burger toppings.