I still remember the first time I tried to recreate a Sonic Double Smasher at home. After countless drive-thru visits, I was determined to master this seemingly simple yet consistently satisfying burger. My first attempts were disappointing until I discovered the secret: proper smashing technique and the perfect sauce.

Copycat double sonic smasher burger on a wood surface.

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After numerous test batches and experimenting with different beef blends, cooking temperatures, and sauce combinations, I finally cracked the code. The result was not just as good as Sonic’s version but even better. The homemade patties had a more substantial beefy flavor, the freshly chopped onions provided the perfect crunch, and my version of the signature smasher sauce took the entire burger to new heights. Now, instead of heading to Sonic when a craving hits, my family requests my homemade version, which has become our go-to burger for weekend cookouts and quick weeknight dinners alike.

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What makes the Sonic Double Smasher so good?

Want a gourmet mushroom burger with fancy cheese and heritage bacon? Sorry, you won’t find that here. But this copycat Sonic Double Smasher burger recipe offers one of the best smash burgers you’ve ever had.

So, what is a Sonic Smasher? It’s Sonic’s version of a classic diner smash burger known for its crispy, thin patties, tangy crinkle-cut pickles, chopped onion, melted cheese, and their signature smasher sauce between a pillowy soft potato bun. There is absolutely nothing fancy here, just an old-school cheeseburger done right. But my, oh, my, how simply delicious it is.

Why you should try this recipe

Better quality – Use superior ingredients than what fast food chains typically offer
Perfectly crispy edges – Proper smashing technique creates the ideal texture
Customizable – Adjust the doneness and toppings to your preference
Budget friendly – Make four burgers for the price of one or two from the drive-thru
No wait time – Skip the drive-thru line and make these whenever you want
Signature sauce – The homemade smasher sauce elevates the entire burger
Simple ingredients – Uses common items you likely already have in your kitchen

Double Sonic Smasher ingredients

For the Sonic Smasher Sauce, you’ll need:

Mayonnaise – Creates the creamy base that holds all sauce ingredients together
Ketchup – Adds tanginess and a touch of sweetness to balance the sauce
Yellow mustard – Contributes classic burger flavor and slight acidity
Dijon mustard – Provides a more complex, deeper mustard flavor
Smoked paprika – Adds subtle smokiness without using actual smoke
Ground black pepper – Gives the sauce a gentle heat and depth
Worcestershire sauce – Creates umami richness and enhances the beefy flavor
White sugar – Balances the acidity and brings all flavors together

For the Sonic Smasher Burger, you’ll need:

Ground beef – The foundation of the burger; 85/15 blend offers the perfect balance of flavor and texture
Unsalted butter – Used for toasting the buns, creating a rich flavor and preventing sogginess
Potato buns – Soft yet sturdy enough to hold all components without falling apart
American cheese – Melts perfectly and provides that authentic fast food burger taste
Yellow onion – Adds sharp flavor and essential crunch to contrast with the soft bun and beef
Crinkle-cut pickle slices – Bring acidity and brightness that cuts through the richness
Salt – Enhances the natural beef flavor and creates a delicious crust
Ground black pepper – Adds gentle heat and complexity to the burger patties

You can use 80/20 ground chuck, but a leaner 85/15 blend will get rid of some of the grease without drying out the patties.

Copycat double sonic smasher burger ingredients on a tray.

How to make it

To prepare the Sonic Smasher Sauce:

In a small mixing bowl, whisk together all the Smashsauce ingredients.
Cover the bowl with plastic wrap and place it in the fridge until needed. You can make the smashsauce a day in advance for a more intense flavor.

To cook the patties:

Divide the ground beef into eight loose equal balls and set them off to the side. Don’t press the meat too firmly while forming the balls, or the burgers will be too dense.
Heat a flat griddle or large cast iron skillet over high heat.
Once the cooking surface is hot, place a ball of meat on it and press it down with a greased spatula or burger press. It is essential to press the meat a few seconds after placing it on the cooking surface to keep from squeezing all the juice out of it. Repeat with a few of the other balls of burger meat, but don’t overcrowd the cooking area.
Season the top of the smashed patties with salt and ground black pepper.
Cook the patties until the edges are dark brown and crispy.
Flip the burgers and season the cooked side with salt and ground black pepper.
Add a slice of cheese and cook the patties for another 30 seconds. Remove to a plate.
Repeat with any remaining patties.

To assemble the Sonic Smasher burger:

Spread the softened butter on the inside of the buns and toast in a dry skillet over medium heat. Place toasted buns off to the side.
While the buns are toasting, dice the yellow onion into small pieces. Keep the diced onion for later.
Spread the Smashsauce on the bottom bun.
Pile the two cooked patties with cheese on top.
Sprinkle on the diced yellow onions and add four pickle slices.
Spread the Smashsauce on the top bun and then close the sandwich.
Serve immediately.

Making copycat double sonic smasher burger.

Homemade Sonic Double Smasher Burger

Skip the drive-thru and create Sonic's famous Double Smasher at home! With perfectly smashed beef patties, melty American cheese, fresh toppings, and homemade Smasher sauce, this copycat version is even better than the original.

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Course: Main Course

Cuisine: American

Keyword: Sonic Recipes

Prep Time: 15

Cook Time: 20

Total Time: 35

Servings:

Calories: 802kcal

Author: Stephanie Manley

Ingredients

Sonic 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

Burger

4 potato buns
1 tablespoon softened butter
1 1/2 pounds ground beef 80/20 ground chuck is preferred
salt and pepper to taste
8 slices American cheese
16 refrigerated crinkle-cut round pickles like Claussen
1/4 cup diced yellow onion

Instructions

To make the Smasher sauce, combine all the ingredients in a small bowl. Mix thoroughly and set aside to let the flavors develop.
Spread 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 8 equal portions and form each portion into a loose ball.
Heat a large griddle or cast-iron skillet over high heat until it’s very hot. Place a beef ball on the hot surface and immediately smash it very thin with a spatula or burger press. Season generously with salt and pepper. Cook for 1 to 2 minutes until the edges become crispy. Flip the patty, season the other side with salt and pepper, and top each patty with a slice of cheese. Cook for another 30 to 45 seconds until the cheese begins to melt. Repeat this process with the remaining patties.
To assemble each burger, place a bottom bun on the plate and spread it with Smasher sauce. Add 2 cheese-topped patties 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.

Nutrition

What to serve this with?

For this old-school Sonic Smasher, keep the sides simple. Here are a few suggestions you can try:

Onion Rings. Lightly battered and fried until crispy, this copycat onion ring recipe from Sonic makes simple and extra-crispy onion rings. If you prefer something a bit heartier, you may prefer a hearty beer batter of Simon and Seafort’s Onion Rings instead.

Loaded Baked Potato Tater Tots. French fries just can’t compete with these homemade tater tots. Inspired by the ones at The Cheesecake Factory, these Loaded Baked Potato Tater Tots are brimming with melted cheese, savory bacon bits, and chopped green onions. You’ll never want to buy frozen tots again after you try these!

Sonic Strawberry Lemonade. You deserve something a whole lot better than soda to wash down a Sonic Double Smasher, and the chain’s famous Strawberry Lemonade is the perfect choice. Its sweet and tart flavor is the ideal thirst-quencher on a hot summer day, or really, anytime.

Two copycat double sonic smasher burgers.

How to store the leftovers

If you haven’t assembled the burgers already, store the cooked patties and the Smashsauce separately inside two airtight containers in the fridge. Take apart an assembled Sonic Smasher burger, wipe off the Smashsauce, and remove the toppings before storing each component inside separate containers in the fridge.

What is the best way to reheat a Double Smasher?

Warm both sides of buns in a skillet over medium heat. Reserve the buns for later.

To warm up the patties, lightly oil a preheated skillet over medium heat. Add the patties with cheese and cover. Cover the top of the skillet, leaving a small opening for some of the steam to escape. Cook the patties until the cheese re-melts, not more than 90 seconds.

Reassemble burgers and serve.

Four copycat double sonic smasher burgers on a wood surface.

More Sonic copycat recipes

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Check out my easy recipes for burgers and the best copycat fast food recipes here on CopyKat!

Enjoy this incredible copycat version of Sonic’s famous Double Smasher! With perfectly smashed patties that create those coveted crispy edges, melted American cheese, fresh toppings, and the signature Smasher Sauce, you’ll craft a burger that rivals or even surpasses the original. The beauty of making these at home is the ability to use higher quality ingredients and customize to your exact preferences. Once you master the smashing technique, you might find yourself making these delicious yet straightforward burgers a regular part of your meal rotation.