For a next-level lunch experience, skip the In and Out and head over to your backyard grill to make my Flying Dutchman Smashburger recipe. Expect a world of flavor with this twist on the classic burger joint cheeseburger. 

Flying Dutchman Smashburger with a generous serving of tater tots.

In case you haven’t heard of the viral Flying Dutchman Burger yet, it’s In and Out’s not-so-secret menu item. Instead of buns, their delicious burgers are smashed between thick onion slices.

The cooking process for the meat is the same as for traditional burgers. The result is a juicy burger with melted American cheese, sauced to perfection — without all the carbs! 

Why You’ll Love the Flying Dutchman Smashburger Recipe

Onion buns instead of hamburger buns? Say what? With a killer homemade burger sauce? Yes, yes! Your taste buds are in for a surprise. If you love fast food but not the carbs, this recipe is so freakin’ delicious! It’s a great option when you’re craving a good burger. 

A close up shot of the dipped Smashburger

If you love Smashburgers and don’t mind the carbs, you may want to check out these recipes: Chorizo Smashburgers, Jalapeño Popper Smash Burgers, Chili Cheese Smash Burgers or Beer Cheese Smash Burgers.

Best Smash Burger Recipe Ingredients 

  • Beef – The 85/15 burger meat is seasoned with my signature trio: kosher salt, black pepper, and then garlic powder. We’ll then drizzle on some yellow mustard for added flavor and zest. 
  • Burger Sauce – The special sauce comes together quickly with some mayo, ketchup, relish, vinegar, and some of my FYR Red Hot Sauce

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  • Cheese – A slice of American cheese on every sliced onion helps keep the “buns” from falling apart. 
  • Onion Buns – Yellow onions, thickly sliced, make up the “bun” portion of the Flying Dutchman Smashburger. Cooking them in some beef tallow then adds to the depth of flavor you’re looking for. For another flavor twist, try making these homemade smash burgers with red onions. 

How to Make the Perfect Smash Burger

Alright, let’s break this ground beef burger recipe down into some easy steps.

First up, in a small bowl, mix up the special sauce for the Flying Dutchman Smashburger. Next, throw it in the fridge to chill while you’re grilling. 

Now, for the onion bun prep. With a sharp knife, slice them into one-inch-thick slices. 

Fire up the grill to a fiery 450 degrees F, for some direct cooking action. 

The Smashburger Recipe starts with beef balls smashed down to thin patties.

Now, let’s get to the burger patties. Take a handful of ground meat and then turn it into a quarter-pound ball of meat. Do that about 6-8 times until you run out of meat.

Toss a large cast-iron skillet on the flames until it gets a bit smoky, around 450 degrees F. Add a burger ball to the hot surface, cover it with parchment paper, and then smash it with a firm metal spatula until it’s a thin patty.

Sprinkle some salt, pepper, and garlic. Let it sizzle for less than two minutes. 

Before flipping, hit it with some drizzles of yellow mustard. Flip a burger, season the new side, add cheese, and let the slice melt for 1-2 minutes. Take it off and let it rest. Repeat for the other patties.

The onion buns are topped with American cheese on the grill.

Carefully place your sliced onions onto the grill with a small amount of oil (or, better yet, some beef tallow) for 2 minutes per side. When they’re looking brown and beautiful, top ’em with a slice of cheese and let the cheese melt. 

Now, assemble your Flying Dutchman Smashburger masterpiece. Onion slice for the bottom bun, special sauce, smash burgers, more sauce, and another onion slice to make up the top bun. Boom, you’re done.

Serve these messy bad boys up, dig in, and enjoy!

What to Serve with the Flying Dutchman Smashburgers

Since you may have a hard time keeping these restaurant burgers from falling apart, make may want to serve them with paper towels instead of napkins. Beyond that, a massive amount of tater tots or some cooked French fries would complete the good smash burger meal.

Serve with dill pickles and, if you are feeling extra adventurous, more of your favorite burger toppings are always welcome. 

The finished masterpiece, a low-carb cheeseburger inspired by In and Out Burgers.

Leftovers & Reheating Flying Dutchman Smashburger

Once you’ve had your fill, store any leftover smash burgers in an airtight container in the refrigerator. If you’ve already assembled your burger with toppings, consider disassembling it to store the components separately.

Ideally, consume the leftovers within 2-3 days for the best taste and texture. Grill up some fresh onions to then make more buns for round two.

More Smash burgers and Tacos


Is it necessary to use a cast iron skillet for this recipe?

While a cast iron skillet adds a nice touch to the smoky flavor, you can use a regular skillet or a hot griddle if that’s what you have on hand. The key is getting it hot enough to achieve that crispy, caramelized sear on the burger. Adjust the heat accordingly and keep an eye on the burgers as they cook.

Can I use pre-made burger patties for the Flying Dutchman Smashburger?

Absolutely! While the recipe guides you through making your own burger balls, you can totally go for pre-made patties if you’re short on time. Just make sure they’re not too thick; the smashing technique works best with thinner patties.

What can I substitute for yellow mustard in the recipe?

Feel free to get creative with your condiments! If you’re not a fan of yellow mustard, you can try using Dijon mustard, spicy brown mustard, or even a tangy barbecue sauce for a different flavor profile. Experiment and find what tickles your taste buds.

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The Flying Dutchman Smashburger is easy to make on the grill.

Flying Dutchman Smashburger

Have you heard of the viral Flying Dutchman Smashburger recipe yet? It's a juicy burger with melted American cheese, sauced to perfection, layered between two grilled onions. Yeah, you heard that right – and it's so freakin' delicious!
Author:Derek Wolf
5 from 2 votes
Prep Time: 15 minutes
Cook Time: 30 minutes
Total Time: 45 minutes
Course: Dinner, Lunch
Cuisine: American
Servings: 4 people



  • 2 lbs Ground Beef 85/15
  • 1.5 tbsp Kosher Salt
  • 1.5 tbsp Black Pepper
  • 1.5 tbsp Garlic Powder
  • Yellow Mustard as needed

Burger Sauce:

  • ½ cup Mayonnaise
  • ½ cup Ketchup
  • 2.5 tbsp Relish
  • 2 tbsp White Vinegar
  • 1 tbsp FYR RED Hot Sauce


  • 3-4 Yellow Onions
  • Sliced American Cheese
  • Cooked Fries/Tater Tots serving
  • Beef Tallow as needed


  • In a bowl, mix all the ingredients for the special sauce then place in the fridge until ready to use.
  • Slice your onions into 1” thick onion slices as a whole to use as your “buns”.
  • Heat your grill to high heat (around 450 degrees F) for direct cooking.
  • Grab a handful of ground beef (around 1/4 lbs… ish) and gently roll it into a ball. Repeat this for 6-8 balls or until you’re out of meat.
  • Add a cast iron skillet or plancha over the flames to heat till it's slightly smoking (about 450 on the skillet).
  • Add a burger ball to the skillet. Place a piece of parchment over one ball and then firmly press with the spatula until the burger is “smashed” on the skillet.
  • Season the patty with salt, pepper, and garlic. Let cook for another 1-1.5 minutes. Before flipping, drizzle some yellow mustard on the unflipped patty.
  • Carefully flip the burger patty over and then season the new side. Top with a slice of cheese and let melt for 1-2 minutes.
  • Once melted, pull off and rest. Repeat for the rest of your patties.
  • Add your sliced onions to cook for 2 minutes per side. Once browned, top with a slice of cheese and let melt.
  • Build your burger with onion slice, burger sauce, smash burgers, more sauce and another onion slice. Serve and enjoy!



Serving: 8Oz | Calories: 902kcal | Carbohydrates: 33g | Protein: 42g | Fat: 67g | Saturated Fat: 21g | Polyunsaturated Fat: 14g | Monounsaturated Fat: 25g | Trans Fat: 3g | Cholesterol: 173mg | Sodium: 3428mg | Potassium: 1076mg | Fiber: 3g | Sugar: 19g | Vitamin A: 208IU | Vitamin C: 16mg | Calcium: 112mg | Iron: 6mg

Derek Wolf

Derek is the driving force behind Over the Fire Cooking. He started cooking with live fire in 2016 and decided to start a social media page so his friends and family could follow the journey. Fast forward to today and Over the Fire Cooking has spread across multiple platforms with millions now following Derek's fire cooking journey. He's a southern fellow who enjoys everything from classic BBQ to Central and South American inspired dishes. Whatever he's cooking up, it's guaranteed to be so freakin' delicious!

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