Blackened Mahi-mahi Sandwich Recipe

Prep Fish

Pat the mahi-mahi fillets dry with paper towels. If fillets are large, cut into 4 roughly equal portions (about 4–6 oz each).

Make Spice Mix

In a small bowl combine smoked paprika, black pepper, kosher salt, garlic powder, onion powder, dried oregano, and cayenne. Mix thoroughly.

Brush both sides of the fillets lightly with 2 tbs olive oil, then press the blackening spice evenly onto both sides of each fillet so they are well coated.

Heat a large cast-iron skillet or heavy nonstick pan over medium-high heat until very hot (about 3–4 minutes). Add a thin film of oil if the pan is not well seasoned.

Add fillets to the hot pan (do not crowd) and sear 2–3 minutes on the first side until a dark crust forms. Flip carefully and cook another 2–3 minutes until opaque and flaky (internal temperature about 145°F / 63°C). Transfer to a plate and let rest 2 minutes.

While the fish rests, combine mayonnaise, chopped dill pickles, chopped capers, minced shallot, fresh dill, lemon juice, Dijon mustard, black pepper, and salt in a small bowl.

Taste and adjust seasoning — add more lemon for brightness, more dill for herbiness, or a pinch of sugar if you want to tame acidity. Refrigerate until assembly (can be made up to 24 hours ahead).

Toast buns: Spread butter on cut sides of buns. Heat a skillet over medium heat and toast buttered sides until golden, about 1–2 minutes. Keep warm.

Assemble sandwiches: On the bottom bun, spread 1–2 tbs of dill tartar sauce. Add a generous handful of spring mix, then place a blackened mahi-mahi fillet on top. Add a tomato slice, 2 pickle slices, and a few rings of red onion. Top with another small dollop of tartar sauce and the bun top.

For plating, serve extra spring mix lightly dressed on the side or piled on the sandwich per preference.

Prepare fries according to package instructions: For oven-baked fries, toss with 2 tbs vegetable oil and spread in a single layer on a baking sheet; bake at 425°F (220°C) for 18–25 minutes, turning halfway, until golden and crispy. For deep frying, heat oil to 350°F (175°C) and fry until golden, 3–5 minutes, then drain on paper towels.

Season fries with salt immediately after cooking and serve alongside the sandwiches.