Some recipes earn a permanent place in the dinner rotation, and this Brasserie Burger is one of those in our home. It’s the kind of meal everyone gets excited about—simple enough for a weeknight, yet special enough to serve when friends and family gather around the table. Rich, comforting, and full of flavor, this burger feels a little elevated without being fussy. Whether you’re cooking for your family or entertaining guests, it’s one of those recipes that never fails to impress and always leaves everyone asking when you’re making it again.

WHAT YOU’LL NEED TO MAKE THESE DELICIOUS BURGERS

• GROUND MEAT: I love using a combination of beef, pork, and veal for these burgers. The blend creates a patty that is incredibly juicy, tender, and flavorful, with a richness that takes it beyond your average burger. Shortcut: My go-to shortcut is Wahlburgers Meatball & Meatloaf Blend, a convenient blend of beef, pork, and veal that’s ready to use and perfect for creating juicy, flavorful burgers without any extra prep.
• EGG: The egg acts as a binder, helping hold the patties together while contributing to their tender texture.
• BREAD CRUMBS: Bread crumbs work alongside the egg to create a burger that stays moist and holds its shape beautifully during cooking.
• WORCESTERSHIRE SAUCE: A splash of Worcestershire adds depth and savory umami flavor, enhancing the natural richness of the meat without overpowering it.
• FRESH GARLIC: Fresh garlic brings a subtle aromatic flavor that complements the beef and adds another layer of savory goodness.
• KOSHER SALT & BLACK PEPPER: Simple seasonings are all that’s needed to let the quality of the ingredients shine while bringing out the best in every bite.
• SWEET ONION: Slowly cooked sweet onions develop a rich, caramelized sweetness that adds incredible flavor and a touch of elegance to the finished burger.
• WHITE MUSHROOMS: Mushrooms provide a hearty, earthy flavor that pairs beautifully with the caramelized onions and adds a brasserie-inspired touch.
• BUTTER: A little butter helps transform the onions and mushrooms into something truly special, creating rich flavor and that irresistible golden caramelization that makes this burger such a favorite.
• GRUYÈRE CHEESE: Gruyère is what gives this burger its brasserie-inspired character. This classic Swiss cheese has a rich, nutty flavor and melts beautifully, creating a creamy layer that perfectly complements the savory burger and sweet caramelized onions. It adds just the right touch of sophistication while still feeling comforting and approachable.
• BRIOCHE BUNS: A great burger deserves a great bun, and brioche is my favorite choice. Its soft, buttery texture and slight sweetness complement the savory flavors of the burger while holding up beautifully to all the delicious juices. Toasting the buns adds just the right amount of texture and helps create that restaurant-quality finish.

Jump to printable recipe for precise measurements

STEP-BY-STEP INSTRUCTIONS

Step 1: In a large mixing bowl, beat the egg until smooth. Mince the fresh garlic and add it to the egg mixture. Add the Worcestershire sauce, salt, and pepper, then whisk everything together until well combined.

Step 2: Add the ground meat blend and bread crumbs to the bowl with the egg mixture. Using your hands or a fork, gently mix until all of the ingredients are evenly incorporated. Be careful not to overmix, as this can result in a denser, tougher burger. Mix just until everything comes together.

Step 3: Divide the meat mixture into 4 equal portions and gently form into patties, making them slightly larger than your buns since they will shrink a bit as they cook. Use your thumb to create a small indentation in the center of each patty—this helps them cook evenly and prevents them from puffing up in the middle. Place the patties on a plate or baking sheet and set aside while you prepare the toppings.

Step 4: While the burger patties rest, heat the butter and a drizzle of extra virgin olive oil in a large skillet over medium heat. Once the butter has melted, add the sliced sweet onions and stir to coat them in the butter and oil. Cook the onions slowly, stirring occasionally, until they become soft, golden brown, and deeply caramelized, about 25–30 minutes. If the onions begin to brown too quickly, reduce the heat and continue cooking low and slow. The goal is to develop their natural sweetness and rich flavor. Transfer the caramelized onions to a bowl and set aside.

Step 5: While the onions are caramelizing, heat the butter and a drizzle of extra virgin olive oil in a separate skillet over medium heat. Add the sliced mushrooms and season with salt and pepper. Sauté the mushrooms, stirring occasionally, until they release their moisture and become tender and golden brown, about 8–10 minutes. Continue cooking until any excess liquid has evaporated and the mushrooms develop a rich, savory flavor. Remove from the heat and set aside until ready to assemble the burgers.

Step 6: Preheat your grill to medium-high heat. Once hot, place the burger patties on the grill and cook for about 4–5 minutes per side, flipping only once. Cook until the burgers reach your preferred level of doneness:

• Medium-Rare: 130–135°F
• Medium: 140–145°F
• Medium-Well: 150–155°F
• Well Done: 160°F

For the most accurate results, use an instant-read thermometer inserted into the center of the thickest part of the burger. Avoid pressing down on the patties while they cook, as this releases the flavorful juices. During the last minute of cooking, place a slice of Gruyère cheese on each burger patty. Close the grill lid and allow the cheese to melt until smooth and creamy. At this time you can also add the buns to the top tier of your grill to toast slightly. Remove the burgers from the grill and let them rest for 3–5 minutes before assembling. This brief rest allows the juices to redistribute throughout the burger, ensuring every bite is tender and flavorful.

Step 7: While the burgers are resting, prepare the tangy sauce. In a small bowl, combine the mayonnaise, ketchup, and Dijon mustard. Stir until smooth and fully incorporated. Taste and adjust the proportions to your preference. For a tangier sauce, add a little more Dijon mustard; for a touch more sweetness, add a bit more ketchup. This simple sauce adds a creamy, tangy finish that ties all of the flavors together and gives the burger that classic brasserie-style touch.

Step 8: To assemble the burgers, spread a generous layer of the tangy sauce on the top and bottom halves of each toasted brioche bun. Place the grilled burger topped with melted Gruyère on the bottom bun. Top with a generous spoonful of the caramelized onions followed by the sautéed mushrooms. Finish with the top bun and serve immediately while everything is warm and the cheese is perfectly melted.

A FAVORITE PAIRING

These burgers pair beautifully with a classic potato salad, making for a meal that’s both comforting and company-worthy. The creamy, tangy flavors of potato salad complement the rich burger and savory toppings without competing for attention. It’s our favorite way to serve this recipe, whether we’re enjoying a casual weeknight dinner or hosting friends for a backyard gathering.