Check the lump crab meat for any bits of shell and pick them out. In a large bowl, gently flake the crab meat into large chunks—avoid overworking so cakes remain tender.

Mix binding ingredients

In a separate bowl, whisk together 1/4 cup mayonnaise, 1 tbsp Dijon, 1 tbsp lemon juice, 1/2 tsp Worcestershire, 1 lightly beaten egg, 2 tbsp chopped parsley, sliced scallions, 1 tsp Old Bay, 1/2 tsp salt and 1/4 tsp black pepper until combined.

Combine and form

Fold the mayonnaise mixture into the crab meat gently. Add 3/4 cup breadcrumbs (or panko) and fold just until mixture holds together when pressed. Do not overmix. Divide into 4 even portions (about 5–6 oz each) and form into round patties roughly 3 1/2 inches wide and 3/4–1 inch thick. Place on a tray, cover, and chill 20–30 minutes to firm — this helps them hold during cooking.

Pan-sear the cakes

Heat a large skillet over medium heat. Add 1 tbsp neutral oil and 2 tbsp butter. When butter foams and is hot (but not burning), add crab cakes, leaving space between them. Cook 3–4 minutes per side until golden brown and crisp, turning carefully with a spatula. If cakes are browning too fast, lower heat to medium-low and cook a few minutes longer to heat through. Internal temperature should reach 145°F (63°C) or hot throughout.

Keep warm

Transfer cooked cakes to a wire rack set over a baking sheet and tent loosely with foil to keep warm while you prepare buns and sauce.

Tartar Sauce

In a small bowl, combine 1/2 cup mayonnaise, 2 tbsp finely minced dill pickle, 1 tsp chopped capers, 1 tbsp lemon juice, 1/2 tsp Dijon mustard, 1 tsp minced fresh dill or parsley, 1/4 tsp black pepper and 1/8 tsp salt. Stir until smooth, taste and adjust seasoning or lemon as needed. Chill at least 10 minutes to let flavors meld.

Sandwich Assembly

Toast and prepare buns

Split brioche buns and lightly butter the cut sides with about 1 tsp softened butter each (optional). Toast in a skillet or under a broiler until golden, about 1–2 minutes. Remove and keep warm.

Season tomatoes and greens

Slice tomato into 4 even slices. Toss mixed greens lightly with a pinch of salt (about 1/4 tsp divided) and a grind of black pepper (about 1/8 tsp) or leave plain, to taste.

Assemble sandwiches

Spread about 1 to 1 1/2 tbsp tartar sauce on the bottom half of each toasted bun. Place a handful (about 1 cup) of mixed greens on the bottom bun, add a slice of tomato, then place a warm crab cake on top. Spoon another 1 tbsp tartar sauce over each crab cake (or serve extra on the side). Top with the bun tops and press gently.

Serve

Serve immediately with lemon wedges on the side for squeezing over the crab cakes. Offer extra tartar sauce on the side. Recommended accompaniments: fries, coleslaw, or a simple pickle.