Japanese Wagyu Smash Burger with Wasabi Aioli

This Japanese Wagyu smash burger is a flavor-packed dinner that comes together in under 30 minutes. Two ultra-thin patties are seared until their edges are crispy and lacy, then topped with melted aged cheddar and sweet caramelized onions.

A zesty wasabi aioli—made with Kewpie mayo, wasabi paste, soy sauce, and furikake—adds a bright, spicy kick. All of it is tucked into a toasted brioche bun that soaks up the rich juices. It's a restaurant-quality burger you can make at home on a hot cast iron griddle.

Smash burgers are all about technique: pressing cold, loosely packed beef onto a screaming-hot surface creates maximum browning and those coveted crispy edges. This version uses ground Wagyu, known for its rich marbling and buttery flavor, which makes every bite incredibly tender.

The wasabi aioli cuts through the richness with a zesty, slightly spicy note, while caramelized onions add sweetness. The result is a burger that's juicy, crunchy, and full of umami—a perfect weeknight treat or weekend indulgence. Follow the steps carefully to achieve the ideal crust and melty cheese.

Ingredients

Why this recipe works

The smash technique is key: pressing the beef paper-thin increases the surface area in contact with the hot griddle, promoting the Maillard reaction. This creates a deep, beefy crust and those crispy, lacy edges that define a great smash burger. Because the patties are thin, they cook quickly, keeping the interior juicy and tender.

Using ground Wagyu elevates the flavor with its high fat content, which renders out during cooking and bastes the meat, adding richness.

The wasabi aioli provides a bright, spicy contrast that balances the fat, while the caramelized onions contribute a deep sweetness. Together, these elements create a harmonious balance of textures and tastes.

Notes and substitutions

Ground Wagyu is available at many specialty butcher shops or online. If unavailable, use high-fat ground beef (80/20) for a similar result. Keep the beef balls chilled until ready to smash—cold meat presses better and holds together. Use a heavy steel press or a sturdy spatula to flatten the patties firmly and quickly.

Kewpie mayonnaise is a Japanese mayo with a richer, tangier flavor than regular mayo. If you can't find it, mix regular mayo with a pinch of sugar and rice vinegar.

Wasabi paste can be found in the Asian foods aisle; adjust the amount to your heat preference. Furikake is a Japanese seasoning blend that adds umami and a subtle crunch—substitute with sesame seeds and nori if needed.

• Kewpie mayonnaise: Regular mayonnaise with a pinch of sugar and rice vinegar
• Wasabi paste: Horseradish mixed with a little soy sauce
• Aged cheddar: American cheese or Gruyère
• Brioche bun: Potato roll or milk bun

Equipment

• Cast iron griddle or heavy skillet
• Heavy steel press or spatula
• Mixing bowl
• Whisk
• Ramekin
• Toaster or oven for bun