Discover the secret behind Sonic’s irresistible Smasher Burgers with this spot-on copycat of their legendary sauce. This isn’t your ordinary burger condiment; this multi-layered sauce combines the creamy richness of mayonnaise with the tangy brightness of ketchup, elevated by yellow and Dijon mustards for complex flavor depth. A touch of smoked paprika and Worcestershire sauce adds sophisticated umami notes that transform any burger from good to crave-worthy. Best of all, this restaurant-quality sauce comes together in just minutes with ingredients you likely have in your pantry.
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This is why you’ll want to have Smasher Sauce on everything
Pssst… do you want to know the secret to the great-tasting Smasher Burgers at Sonic? It’s in the sauce. Smasher Sauce is unique to fast food burgers because it is more than just a gussied-up salad dressing.
So, what is Sonic Smasher Sauce, and why should you slather it on your next burger? The recipe starts with the standard mayo and ketchup combo. Then, things get a little different by adding both yellow and Dijon mustards for a flavor twist. A pinch of smoked paprika, a splash of Worcestershire sauce, and a bit of sugar give the sauce the right mix of savory and umami flavors.
This Sonic Smasher Sauce recipe comes together in seconds and is great for more than just burgers! Try it on sandwiches, fries, or anything else that needs a punch of flavor.
Sonic Smasher Sauce ingredients and their roles in the recipe
To prepare this Sonic Smasher Sauce recipe, you’ll need:
- Mayonnaise – gives the burger sauce a creamy richness.
- Ketchup – helps balance out the mayonnaise with a bit of acidity.
- Yellow mustard – brings the classic fast-food mustard flavor.
- Dijon mustard – adds a more refined mustard flavor.
- Smoked paprika – imbues a smoky sweetness and rich color to the sauce.
- Worcestershire sauce – Ups the umami quotient.
- Sugar – sweetens the sauce to keep it from being overwhelmingly acidic.
How to make Smasher Sauce
To prepare the Sonic Smasher Sauce recipe:
- Add all the Sonic Smasher Sauce ingredients to a medium mixing bowl.
- Whisk all the ingredients until they are well combined.
- Transfer the sauce to an airtight container and place it in the fridge for at least an hour before serving. Allowing the sauce to rest allows the flavors to come together.
What to serve with Smasher Sauce
Sonic Smasher Sauce is versatile and can improve the taste of almost everything. Below are a few delicious ways to enjoy it:
Sonic Double Smasher Burger. There are dozens of ways to use Smasher Sauce, but why not start off with one of the best? Sonic Double Smasher Burgers features two thin, beautifully browned patties, tangy pickles, melty American cheese, piquant chopped white onions, and plenty of Smasher Sauce on a soft potato bun. Even if you are a burger brat, this recipe won’t disappoint you.
Onion Rings. Although onion rings may not be as popular as French fries or nachos, they make a great snack or side. And there are so many ways to make them. Maybe you like to cut them extra thick and dunk them in a beer-based batter before frying like they do at Simon and Seafort’s Onion Rings, or perhaps you prefer the Original Sonic Onion Rings’ batter made with melted vanilla ice cream! Either way, onion rings taste better with Smasher Sauce.
Chicken Nuggets. Skip the frozen food aisle and make delicious buggies in your kitchen with this easy-to-follow Homemade Chicken Nuggets recipe. Say goodbye to fillers and preservatives, so you will feel better about giving your kids the chicken nuggets they are asking for. Serve these chicken nuggets with your favorite bowl of sauce, like Smasher Sauce. McDonald’s Hot Mustard Sauce, or Red Robin’s Campfire Sauce.
Storage and how long will this sauce last
- Refrigerator Storage: Store in an airtight container for up to 1 week. Discard any sauce that has been used for dipping to prevent contamination.
- Reheating Method: This sauce is served cold and does not require reheating. Stir gently before using if separation occurs.
- Freezing: Not recommended, as mayonnaise-based sauces separate when frozen and do not restore to their original texture when thawed.
More copycat recipes for fast food sauces
- Arby’s Tzatziki Sauce
- Chick-fil-A Polynesian Sauce
- Popeyes Blackened Ranch
- Subway Baja Chipotle Sauce
- Taco Bell Chipotle Sauce
- Zaxby’s Zax Sauce
Check out my easy recipes for sauces and the best fast food copycat recipes on CopyKat!
Sonic Smasher Sauce
Ingredients
Smasher Sauce
- 2 tablespoons mayonnaise
- 1 tablespoon ketchup
- 1 teaspoon yellow mustard
- 1/2 teaspoon Dijon mustard
- 1/8 teaspoon smoked paprika
- 1/8 teaspoon ground black pepper
- 4 drops Worcestershire sauce
- 1/2 teaspoon sugar
Smash Burgers
- 1 tablespoon softened butter
- 4 potato buns
- 1 pound ground beef 80/20 ground chuck is preferred
- salt and pepper to taste
- 4 slices American cheese
- 16 refrigerated crinkle-cut round pickle slices like Claussen
- 1/4 cup diced yellow onion
Instructions
Smasher Sauce
- Combine all the sauce ingredients in a small bowl. Mix thoroughly and set aside to let the flavors develop.
Smash Burgers
- Spread the softened butter evenly on the cut sides of the potato buns. Place the buns cut-side down on a griddle or skillet and toast until golden brown. Set aside.
- Divide the ground beef into 4 equal portions and form each portion into a loose ball.
- Heat a large griddle or cast-iron skillet over high heat. Once it is hot, place a beef ball on the griddle or skillet and immediately smash it with a spatula or burger press until it is very thin. Season generously with salt and pepper. Cook for 1 to 2 minutes until the edges become crispy. Flip the patty and season the other side with salt and pepper. Top the patty with a slice of cheese and cook for another 30 to 45 seconds until the cheese begins to melt. Repeat this process with the remaining patties.
- To assemble each burger, spread Smasher sauce on a bottom bun and place it on a plate. Add a cheese-topped patty followed by 4 pickle slices and a tablespoon of onions. Spread additional Smasher sauce on the top bun and place it on the burger. Serve immediately while hot.
Wow! This sauce is amazing. It tastes just like Sonic’s and maybe even better. I put it on burgers and dipped my fries into it. Super easy to make too!
Now that it’s just me and my husband at home, we don’t eat out as much — but we still crave those Sonic burgers. This sauce brought all the flavor right to our kitchen. We’ve been using it on burgers, chicken, and even as a dip for onion rings. It’s like a little taste of date night without leaving the house.
These were delicious!