Wagyu Steakhouse Burger Recipe

Thinly slice onion(s) if not already sliced. Heat a large skillet over medium-low heat and add butter and olive oil. Add onions, sprinkle with salt and sugar, and cook gently, stirring every few minutes, for 25–30 minutes until deep golden and soft. If onions begin to stick, add 1–2 tablespoons water. Stir in balsamic vinegar in the last minute, then remove from heat and set aside.

In a medium skillet over medium heat, cook diced bacon until fat renders and bacon is crisp (about 6–8 minutes). Remove most of the rendered fat, leaving about 1 tablespoon in the pan. Add the chopped onion and cook until soft, 4–5 minutes. Stir in brown sugar, maple syrup, and apple cider vinegar. Add water, reduce heat to low, and simmer gently for 8–10 minutes until thick and jammy. Coarsely mash with a fork or pulse briefly in a food processor for a smoother jam. Season with pepper and adjust salt if needed. Keep warm or refrigerate until assembly.

If you don't already have roasted marrow, roast beef marrow bones at 425°F (220°C) for 15–20 minutes until marrow is soft, scoop out 1 tablespoon and let cool slightly. In a small bowl, whisk together mayonnaise, roasted marrow, minced garlic, lemon juice, Dijon mustard, salt and pepper until smooth. Taste and adjust seasoning. Refrigerate until ready to use.

Divide the ground Wagyu into two equal portions (for two burgers) or keep as one large patty depending on desired servings. Gently form into patties about 3/4-inch thick, making a slight indentation in the center to prevent doming. Season both sides liberally with salt and freshly ground pepper just before cooking.

Heat a cast-iron skillet or heavy pan over medium-high heat and add 1 tablespoon neutral oil. When the oil is shimmering, add the patties and sear without moving for 3–4 minutes until a deep brown crust forms. Flip and immediately place a slice of fontina on each patty; cook another 3–4 minutes for medium-rare to medium depending on thickness and preference. Use a thermometer if desired: 125–130°F for rare, 135°F for medium. Remove patties and let rest 3–4 minutes.

Preheat oven to 425°F (220°C) for roasted fries or heat oil to 350°F (175°C) if frying. If roasting: toss cut potatoes with 2 tablespoons vegetable oil and a pinch of salt; spread in a single layer on a baking sheet and roast for 25–30 minutes, flipping halfway, until golden and crisp. If frying: fry in batches until golden and crisp, drain on paper towels and season immediately with salt.

While still hot, toss fries with truffle oil and grated Parmesan. Sprinkle with chopped parsley if using and adjust salt to taste. Keep warm until serving.

Heat a small skillet over medium heat and spread butter on cut sides of brioche buns. Toast cut-side down until golden, about 1–2 minutes.

Spread about 1 tablespoon bone marrow aioli on the bottom bun. Place the rested Wagyu patty with melted fontina on top. Spoon 1–2 tablespoons bacon jam over the cheese. Add 2–3 tablespoons caramelized onions, a few slices of pickles and a small handful of greens (optional). Spread a thin layer of aioli on the top bun and close the burger.

Serve immediately with truffle fries on the side.