Wagyu Burger Recipe

Form patties

Divide the wagyu ground beef into two equal portions (about 8 oz each). Gently form each into a loose patty roughly 3/4"–1" thick, pressing a slight indentation in the center to prevent doming. Handle minimally to keep texture tender.

Season

Lightly season both sides of each patty with kosher salt and freshly ground black pepper immediately before cooking.

Cook

Heat a heavy skillet (cast-iron preferred) over medium-high until very hot. Add 1 tablespoon neutral oil and swirl. Place patties in skillet and cook 3–4 minutes without moving until a deep brown crust forms. Flip and cook 2–3 minutes for medium-rare to medium (internal temperature ~130–140°F / 54–60°C). Reduce time slightly for rarer, slightly longer for more done. Add sliced Gruyère to the patties in the last 1 minute, cover skillet briefly or tent with foil to melt cheese. Remove patties to rest on a warm plate for 3 minutes.

While patties rest, make the au poivre mayo. In a small bowl combine the mayonnaise, coarsely crushed black peppercorns, Dijon mustard, lemon juice, and kosher salt. Taste and adjust seasoning. Refrigerate until assembly. (Can be made up to 1 day ahead.)

Cook shallots

Heat 1 tablespoon butter and 1 teaspoon olive oil in a medium skillet over medium-low heat. Add the thinly sliced shallots and a pinch of salt. Cook slowly, stirring occasionally, until softened and translucent, about 8–10 minutes.

Caramelize

Increase heat to medium and add the granulated sugar. Stir to coat shallots; continue cooking until shallots begin to caramelize, 6–8 minutes, stirring more frequently to prevent burning.

Deglaze & finish

Add the balsamic vinegar and optional red wine to deglaze the pan, scraping up browned bits. Stir in fresh thyme, reduce heat to low, and simmer until mixture is jammy and most liquid has evaporated, about 6–8 minutes more. Season with 1/2 teaspoon kosher salt and 1/4 teaspoon freshly ground black pepper. Remove from heat and cool slightly. Can be made ahead and refrigerated up to 3 days; rewarm gently before serving.

Preheat & toss

Preheat oven to 425°F (220°C) if roasting. Pat sweet potato fries very dry with paper towels. In a large bowl, toss fries with cornstarch until evenly coated, then add 2 tablespoons oil, smoked paprika, garlic powder, kosher salt, and black pepper; toss to coat.

Roast

Arrange fries in a single layer on a parchment-lined baking sheet without overcrowding. Roast 18–25 minutes, flipping once halfway, until edges are crisp and centers tender. If you prefer frying: heat 1" of vegetable oil in a heavy skillet to 350°F (175°C) and fry batches 3–4 minutes until golden, drain on paper towels and season immediately.

Toast buns: Butter the cut sides of the brioche buns with the reserved 1 tablespoon butter and toast in a skillet over medium heat until golden, about 1–2 minutes per side.

Build the burger: Spread about 2 tablespoons of au poivre mayonnaise on the bottom half of each toasted bun. Place the rested Wagyu patty with melted Gruyère on the mayo. Spoon 1–2 tablespoons of shallot jam over the cheese. Top with a generous handful (~1/2 cup) of watercress. Spread a thin layer of mayo on the top bun and place over the burger.

Serve: Plate each burger with a portion of sweet potato fries alongside. Offer extra au poivre mayo and shallot jam on the side if desired.