Brunch Wagyu Smash Patty Burger Recipe

In a small bowl combine mayonnaise, Dijon, lemon juice, grated garlic and coarsely cracked black peppercorns. Stir until smooth and taste; add salt to taste (about 1/4–1/2 tsp). Refrigerate until assembly.

Thinly slice 1 large yellow onion (not listed separately) and melt 1 tbsp butter in a skillet over medium-low. Add onions and a pinch of salt. Cook, stirring occasionally, for 25–30 minutes until deep golden and sweet. If using pre-made caramelized onions, heat gently before assembly.

Cut peeled russet potatoes into very thin shoestring strips (use a mandoline or sharp knife). Rinse in cold water until water runs clear to remove starch. Pat completely dry with kitchen towels.

Heat beef tallow and optional oil in a heavy pot or deep fryer to 325°F (163°C). Working in batches, fry potatoes for 3–4 minutes until just tender but still pale. Remove to a wire rack and drain on paper towel.

Increase oil temperature to 375°F (190°C). Return fries in small batches and fry 1–2 minutes until crisp and golden-brown. Drain on paper towels and immediately season with fine sea salt. Keep warm in a single layer in a low oven (200°F/95°C) if needed.

Preheat oven to 400°F (200°C). Place bacon slices on a rimmed baking sheet lined with foil or parchment and bake 12–18 minutes until crisp to your liking. Drain on paper towels. Alternatively, cook in a skillet over medium heat until crisp.

Divide 1 lb Akaushi ground beef into 8 equal portions (~2 oz each) for double-stack smash patties for 4 burgers (two portions per burger). Lightly shape each portion into loose balls; do not overwork.

Heat a large, heavy cast-iron griddle or skillet over high heat until smoking hot. Brush or rub a thin film of beef tallow or neutral oil on the surface (not listed; use residual tallow if available).

Place each loose ball on the hot surface and immediately press firmly with a heavy spatula or a burger press flattened with parchment to about 1/4" thickness. Season the top with a pinch of kosher salt and a grind of black pepper.

Cook undisturbed for 1.5–2 minutes until edges brown and crisp. Flip and immediately place a slice of Muenster cheese on each patty. Cook the second side 30–60 seconds until cheese melts and patty is cooked through. Stack two patties per bun during assembly.

Heat a nonstick skillet over medium-low and add 1 tsp butter. Crack eggs gently into the pan. Cook slowly until whites are set but yolks remain runny, about 3–4 minutes. Season with a little salt and pepper. For slightly drier whites, cover pan in final 30–45 seconds.

Lightly butter the cut sides of brioche buns (1 tbsp butter total). Toast cut-side down in a skillet or on the griddle over medium heat until golden, about 1–2 minutes.

Spread about 1 tbsp black peppercorn aioli on the bottom bun. Add lettuce leaf, tomato slice, and pickles as desired (LTP). Place two smash patties (stacked) topped with melted Muenster on each bottom bun.

Top patties with 1 slice warmed smoked bacon (or two half-slices), a generous spoonful (~2 tbsp) of caramelized onions, then a sunny-side-up egg. Finish with a little freshly ground black pepper and close with the top bun smeared lightly with additional aioli if desired.

Serve immediately with beef tallow shoestring fries on the side.