Name: Smash Burgers with Mustard Smash Sauce Recipe
Prep time: 5 min
Cook time: 10 min
Total time: 15 min
Cuisine: American
Ingredients: ¼ cup whole-grain mustard; ¼ cup prepared yellow mustard; ¼ cup olive oil mayonnaise; 1 pound (80/20) ground beef; Morton kosher salt, to taste; 4 brioche buns, split; 1 medium yellow onion, very thinly sliced; ½ head iceberg lettuce, leaves separated; 3 large kosher dill pickles, thinly sliced, plus extra for serving; 4 slices American cheese (such as Kraft Singles)

Jump to Recipe· 3.9 from 15 reviews

If you ever find yourself craving a burger that’s bursting with bold flavor and irresistible texture, this Smash Burgers with Mustard Smash Sauce Recipe is exactly what you need. It’s not just any burger; it’s a masterclass in simplicity and punchy flavor, combining the perfect sear of juicy smashed beef patties with a tangy, creamy mustard smash sauce that elevates every bite. Whether you’re cooking for a quick weeknight dinner or a casual weekend feast with friends, this recipe delivers that classic diner-style experience with a delicious homemade twist.

Ingredients You’ll Need

A metal tray holds four raw round beef patties with a rough texture in the top left corner. Below them, there is a neat stack of thin white onion slices on the left side. A small white bowl with three types of sauce white, yellow, and grainy mustard is placed near the onions. Next to the sauces, there are several glossy orange cheese slices stacked in a small pile. Below the cheese, a white bowl is filled with sliced pickles, appearing moist and shiny. On the right side of the tray, four golden brown buns with soft texture are stacked, and beneath them and to the right are fresh green leafy lettuce heads. The tray sits on a white marbled surface. Photo taken with an iphone --ar 4:5 --v 7

These ingredients are straightforward but absolutely essential to bring this classic burger to life. Each component brings its own magic to the table—rich beef with that perfect fat content, a mustard-forward sauce that adds brightness, and fresh toppings for satisfying crunch and color.

¼ cup whole-grain mustard: Adds texture and a sharp, earthy bite that stands out without overpowering.
¼ cup prepared yellow mustard: Provides smooth, tangy flavor that balances the grainy mustard perfectly.
¼ cup olive oil mayonnaise: Gives the sauce a creamy body and a subtle richness.
1 pound (80/20) ground beef: The ideal fat ratio for juicy, flavorful patties that crisp up beautifully when smashed.
Morton kosher salt: Essential for seasoning and enhancing the natural flavors of the beef.
4 brioche buns, split: Soft, buttery buns that toast nicely and hold up to the juicy patties and sauce.
1 medium yellow onion, very thinly sliced: Adds sweetness and a little bite, especially once griddled.
½ head iceberg lettuce, leaves separated: For a refreshing crunch and bright color contrast.
3 large kosher dill pickles, thinly sliced (+ more for serving): Adds acidity and that iconic burger zip.
4 slices American cheese: Melts perfectly over the patties for that classic creamy, gooey finish.

How to Make Smash Burgers with Mustard Smash Sauce Recipe

Step 1: Prepare the Mustard Smash Sauce

Start by mixing together the whole-grain mustard, prepared yellow mustard, and olive oil mayonnaise in a small bowl. This sauce is the key player that brings sharpness and creaminess, creating the perfect partner for the juicy burger. Set it aside while you move on to the patties.

Step 2: Form the Burger Balls

Divide your ground beef into four equal portions, roughly 4 ounces each, then gently roll them into balls. The goal here is not overworking the meat to keep it tender, but still firm enough to smash without falling apart during cooking.

Step 3: Preheat Your Skillet

Place a large 12-inch cast iron or stainless steel skillet over medium-high heat and let it smoke slightly—that intense heat is what gives your burgers those irresistible crusts. While waiting, you can toast your buns for a minute or so, cut side down, until golden to add a buttery crunch.

Step 4: Smash and Sear the Patties

Turn the heat up to high and add two meatballs at a time. Sprinkle them generously with kosher salt and use a heavy-duty spatula, pressing down firmly—if you have a potato masher, use it on top of the spatula for maximum smash. Cook without moving for about 1 ½ minutes to achieve that signature crispy, caramelized bottom.

Step 5: Add Onion and Flip

Press thin slices of onion into the patties, letting them cook right into the beef for extra flavor. Then scrape under the patties and flip them carefully.

Step 6: Cheese and Finish Cooking

Immediately add a slice of American cheese on top of each patty and continue cooking for 30 to 60 seconds until the cheese melts and the onions on the bottom become golden and caramelized. Remove the patties and wipe the skillet clean before cooking the next batch.

Step 7: Assemble Your Smash Burgers with Mustard Smash Sauce Recipe

Spread a generous tablespoon of the mustard smash sauce on both the top and bottom buns. Lay pickle slices on the bottom bun, then the hot burger patty. Add a few raw onion slices and a couple of iceberg lettuce leaves before topping with the bun. Serve with extra pickle spears for that delightfully tangy finish.

How to Serve Smash Burgers with Mustard Smash Sauce Recipe

A close-up view of a burger with a shiny golden brown bun on top, a layer of bright green leafy lettuce just underneath, melted orange-yellow cheese dripping over a thick, dark brown grilled beef patty, pickles and sautéed light brown onions spread with a yellow mustard sauce on the bottom golden brown bun. The burger sits on a light wooden board with some potato chips scattered around. In the background, there is a glass jar with green pickle slices and another burger slightly blurred. The setting shows a white marbled surface behind the food. Photo taken with an iphone --ar 4:5 --v 7

Garnishes

Keep it fresh and crisp by adding extra pickle slices and more thinly sliced onions on the side. A few lettuce leaves add wonderful crunch and brightness to balance the rich beef and sauce. Consider a few sprigs of fresh herbs or a sprinkle of freshly cracked black pepper for an extra flavor lift.

Side Dishes

These burgers pair beautifully with classic sides like crispy French fries, onion rings, or even a fresh coleslaw to add a cool contrast. For something a bit lighter, a simple mixed greens salad with a vinaigrette complements the richness of the burger and mustard smash sauce perfectly.

Creative Ways to Present

Want to impress your guests? Consider serving the Smash Burgers with Mustard Smash Sauce Recipe on mini brioche buns for a party platter, or deconstruct the elements on a board for an interactive build-your-own burger experience. Adding a skewer through the center keeps everything neat and makes it easy to handle!

Make Ahead and Storage

Storing Leftovers

If you have any leftover patties or sauce, store them separately in airtight containers in the fridge. The patties will keep well for up to two days but are best enjoyed fresh to preserve that crispy crust.

Freezing

You can freeze the uncooked meatballs before smashing and cooking. Freeze them on a tray until solid, then transfer to freezer bags for up to three months. The mustard smash sauce, however, should be made fresh for the best flavor and texture.

Reheating

Reheat cooked patties gently in a skillet over medium-low heat to preserve juiciness and try not to overcook the cheese. Warm the buns separately to keep them from getting soggy. Add fresh sauce and toppings after reheating for that fresh-off-the-griddle experience.

FAQs

Can I use other types of mustard in the Smash Burgers with Mustard Smash Sauce Recipe?

Absolutely! While whole-grain and yellow mustard give the sauce its distinctive texture and classic flavor, you can swap in Dijon or spicy brown mustard for a slightly different twist that’s equally delicious.

What’s the best way to get the patties really crispy?

The key is using a heavy-bottomed skillet that can get very hot and smashing the meat balls thinly with a heavy spatula or potato masher without moving them while cooking. This creates the much-loved crust that defines a smash burger.

Can I make these burgers gluten-free?

Definitely! Just use gluten-free buns or lettuce wraps. All other ingredients in the Smash Burgers with Mustard Smash Sauce Recipe are naturally gluten-free, making it an easy swap for those with sensitivities.

Is it okay to use ground turkey or chicken instead of beef?

Ground beef’s fat content is crucial for juiciness and crust formation, so turkey or chicken won’t give the same results. If you want to try poultry, consider adding some fat like bacon or extra oil, but the texture and flavor will vary.

How spicy is the mustard sauce in this recipe?

The combined mustards give the sauce a nice tang and mild heat, but it’s not overwhelmingly spicy. If you want a kick, add a splash of hot sauce or a pinch of cayenne pepper to the sauce for more heat.

Final Thoughts

You really can’t go wrong with this Smash Burgers with Mustard Smash Sauce Recipe. It’s the kind of meal that instantly feels like a treat, yet it’s so easy to make that it quickly becomes a loyal favorite in your cooking rotation. The balance of robust smashed beef, tangy creamy sauce, and fresh toppings is pure magic. Go ahead and give it a try—you’ll wonder why you ever settled for anything less!