Discover the new king of burgers: The Fried Onion Smash Burger. We’ll explain what a smash burger is, how to make it, and our 2 tricks to achieving this savory and delicious creation.

What is a Smash Burger?
Unlike traditional burgers that are formed into nice round even patties, a smash burger is a round ball of ground beef that is smashed onto a smoking hot griddle, creating a thin patty that cooks quickly and develops a crispy, caramelized crust. You may have had one at places like In-n-Out-Burger or Five Guys.
The flattened patty allows for more surface area to be in contact with the griddle, resulting in that coveted charred flavor. As for the fried onions, they add an extra layer of sweetness and texture, taking this burger to a whole new level of deliciousness.
I like to make these outside on my Blackstone – which is a flat top grill. If you don’t have one, a basic griddle will also work. A skillet would not be a good option however. These burgers do best on a large flat surface.

SECRET #1 – PREPPING THE ONIONS
In order for the onions to be done at the same time as the burgers, we need to do a little prep work, and this can be done with just one little step. Salt. Salting the onions draws out moisture, so they will caramelize quicker on the grill.
- Peel the onion and cut off the root on both sides. Cut the onion in half and place the flat side down. Slice it into thin half round circles. Then place the onion slices in a bowl and sprinkle them with ½ – 1 teaspoon of salt. Give them a good stir, cover them and place them in the fridge for 1 hour.
- Strain the onions in a colander and discard the water. Blot them with a paper towel and set aside until ready to grill.

HOW TO MAKE A GRILLED ONION SMASH BURGER
- First, divide a pound of ground beef (80/20 ratio) into four equal portions and roll each into a ball. Preheat a griddle or heavy skillet over high heat until it’s smoking hot. Add some oil to the grill.
- Next, place one ball of beef onto the griddle and use a heavy metal press to SMASH it flat. Your basic kitchen spatula is not the best option for this as it can bend. A heavy duty grill spatula will work, but I like to use a small cast iron pan. See below for our secret to getting the burger not to stick!

- Place the onions right along side and squirt a little more oil on top. Season the meat with salt and pepper and allow the Maillard reaction to take place. The very hot grill will cook these smash burgers in no time. Once you see the edges start to brown and become crispy, quickly slice the spatula between the burger and the griddle to remove it before flipping.
- Flip the patty along with the onions and cook it for another minute or so until it’s cooked to your liking. Top each patty with the onions and a slice of cheese.
- Place some buns on the griddle just before serving for that nice toasted top.
- Place each burger on to a hamburger bun and serve.
SECRET #2
These burgers are absolutely delicious but getting them smashed without sticking to the spatula can be tricky. That’s where a simple piece of parchment paper comes in! Place the ball of beef on the grill, then place the parchment paper over it. Now press down quickly and firmly using a heavy duty spatula or press. Peel the parchment paper off. Wa-laa! No sticking!

FRIED ONION SMASH BURGER RECIPE
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FRIED ONION SMASH BURGER
Description
A thin crispy charred beef patty that has been SMASHED for that perfect sized burger – just like Five Guys!
Ingredients
- 1 lb. Ground Beef (80/20 ratio)
- 1 Large Onion, cut into half moon slices
- 1 teaspoon Sea salt
- Hamburger buns
- Cheese
- Condiments of choice
Instructions
- Peel the outer layer of the onion and cut the root off both ends. Cut the onion in half and place the even side down. Cut the onion in half moon thin slices. Place the onion in a bowl and sprinkle with salt. Mix the onions around. Cover and refrigerate for 1 hour.
- Form 4 even size meatballs with the beef. Place on a plate or platter.
- Tear a square piece of parchment paper.
- Drain the onions and squeeze out any excess moisture. Place in a clean bowl.
- Lightly oil a VERY HOT griddle and place the onions on it. Drizzle a little more oil on top.
- Place the ground beef ball on the grill and put the parchment paper on top. Smash the ball with a heavy duty spatula, small cast iron skillet or press. Peel off the paper and repeat 3 times.
- Cook the burgers undisturbed for 4-5 minutes. Using the side of the spatula, quickly go between the burger and grill to loosen – flip and cook for another 3-4 minutes on the other side. Flip the onions and add more oil if necessary.
- Place the buns on the grill if desired. Add cheese if desired.
- Assemble your burger and enjoy!
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