MSG Smash Burgers Onions

Juicy and deeply savory, these MSG Smash Burgers bring together ultra-crispy beef, buttery sweet onions, and a punchy special sauce for a burger night that rivals any diner or backyard cookout. With minimal fuss and just a few clever touches, this recipe ensures every bite is full of flavor and tender crunch. If you have been craving the ultimate old-school burger experience but want that extra restaurant-level umami, this is the one. The first time I made these, my kitchen filled with the best sizzle and aroma, and now they truly stand as my favorite burger.

I remember the first bite of these burgers at my own stove and how silence fell as everyone took that first big bite. Now these are our most requested at family gatherings.

Ingredients

• Black pepper: brings a warm kick and nice depth to burger salt Use freshly ground for best results
• Kosher salt: balances and enhances all the flavors Choose a salt with clean mineral flavor
• MSG: gives irresistible umami depth I go for high-quality Ajinomoto
• Mayonnaise: forms the creamy base of the sauce Look for full-fat with a clean taste
• Garlic: fresh and grated makes the sauce shine Use firm cloves without green shoots
• Sherry vinegar: brightens the sauce and cuts richness Go for real sherry vinegar if you can
• Smoked paprika: lends subtle warmth and smokiness Spanish smoked paprika is incredible here
• Yellow mustard: keeps the sauce tangy Standard yellow mustard is classic
• Cornichons: add sharp crunch to the sauce Use the smallest snappy ones you find
• Onion: becomes sweet and rich when slowly cooked Slice them evenly for best texture
• Granulated sugar: rounds out the soubise onions Use a pure white type
• Unsalted butter: lifts the onions to rich and silky Choose high-quality for pure flavor
• Ground beef blend: brings a mix of juicy fat and bold beef Use a blend like chuck and brisket
• American cheese: guarantees ultimate melt Look for real deli slices over processed
• Sesame seed hamburger buns: add a tender bite and aroma Go for sturdy but fluffy buns
• Half sour pickles: add brightness and cut through richness Crisp refrigerated ones work best

Step-by-Step Instructions

Make Burger Salt:

In a small bowl stir together black pepper kosher salt and MSG until evenly mixed Set aside for seasoning the patties This blend delivers just the right punch and helps develop that savory crust

Prepare Special Sauce:

In your blender add mayonnaise grated garlic sherry vinegar smoked paprika yellow mustard kosher salt MSG and the soft-boiled egg if you want extra creaminess Blend until totally smooth about one minute Pour this into a bowl and gently fold in the finely chopped cornichons Chill it in the fridge to let the flavors meld The touch of sherry vinegar and paprika gives that secret sauce feel that lingers

Cook Soubise Onions:

Toss sliced onions with sugar and kosher salt right in your saucepan Let them sit for thirty minutes at room temperature This draws out their moisture Add the cubes of butter and cook over medium heat stirring every several minutes The onions should soften and turn translucent without getting browned about twenty five to thirty minutes Turn off the heat and set them aside They should taste sweet and melty with no color

Form and Smash Burgers:

Portion your ground beef into eight even balls about four ounces each Heat up a cast iron skillet or griddle over medium high until nearly smoking Working in batches space out the meat balls at least three inches apart Spray your metal spatula with cooking spray and use it to firmly flatten each ball until thin but not broken up about one third inch thick If you have a burger press and parchment use those for easier smashing

Season and Cook Patties:

Once the patties are smashed sprinkle the tops with your reserved burger salt Let them sear untouched for about two minutes until the bottoms are beautifully browned and crispy Flip them gently with a sturdy spatula Sprinkle again with a pinch of burger salt and quickly top each patty with a slice of American cheese Sear for another two minutes until the cheese melts and the burgers are cooked through

Assemble and Serve:

Spread a layer of those sweet soubise onions on the bottom halves of your toasted buns Stack on two patties per burger and spoon over a generous amount of the special sauce Top with four or five slices of pickle and cap with the top bun Serve immediately while everything is piping hot and gooey

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The soubise onions are my secret weapon here Their slow melting sweetness wraps the smoky beef in an unbelievable hug The buttery aroma reminds me of summer cookouts when my cousins and I hovered near the stove just hoping for a taste

Storage Tips

Wrap leftover burgers tightly and store in the fridge for up to two days To reheat place in a covered skillet over low heat until warmed through For onions and sauce keep each in airtight containers for up to four days Freezing is not recommended for best texture but the burger patties themselves can be frozen before smashing and cooked directly from frozen

Ingredient Substitutions

You can swap out the ground beef with ground turkey for a leaner choice though you may lose some of the richness If you do not have MSG simply use a bit more kosher salt and smoked paprika For the cheese try mild cheddar or Colby for a more classic American burger Melt quality is everything so avoid pre shredded cheese

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Serving Suggestions

These burgers beg for crispy fries or golden onion rings Serve with a cold crunchy slaw or just a heap of napkins and lemonade For extra zing layer a few pickled jalapeños or thin slices of red onion into the sandwich A little extra sauce on the side never hurt anyone

Cultural and Historical Context

Smash burgers trace their roots to early griddles and diners in the Midwest where cooks learned that smashing beef on a hot pan created a savory browned crust and juicy center MSG is a staple in Asian cooking but its inclusion here is a nod to the umami flavor boost that turns simple burgers into craveable favorites This recipe is a fun collision of American and global comfort food traditions

Recipe FAQs

→ What makes the burger patties extra flavorful?

The burger blend uses a mix of ground chuck and brisket, seasoned with a burger salt that includes MSG for enhanced savory depth.

→ How are the soubise onions prepared?

Thinly sliced onions are slowly cooked with butter and sugar until soft and translucent, resulting in a rich, buttery topping.

→ What is the key to smashing the patties correctly?

Use a heavy metal spatula to press each ball of ground beef firmly into a hot skillet, creating crispy, brown edges and sealing in juices.

→ How is the special sauce made?

Creamy mayonnaise is blended with grated garlic, sherry vinegar, smoked paprika, mustard, pickles, and MSG for a tangy, punchy sauce.

→ Can the burgers be made in advance?

They are best enjoyed fresh off the skillet for maximum crispiness, but components like soubise onions and special sauce can be made ahead.

→ What toppings work best?

Classic American cheese, buttery onions, tangy sauce, and crisp half-sour pickles come together for balanced flavor and texture.