Jul 14 2026
RestaurantsBelle'sBlackened Mahi Mahi Sandwich Recipe

Blackened Mahi Mahi Sandwich Recipe

Inspired by Belle's
Time35m
Serves4

lettuce, tomato & island tartar sauce

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Ingredients

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For the blackened mahi mahi

Method

For the blackened mahi mahi

  1. 1

    Prepare fillets

    Pat mahi mahi fillets dry with paper towels and cut into four sandwich-sized portions if not already portioned. Lightly brush both sides with 2 tbs olive oil.

  2. 2

    Make blackening spice

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

  3. 3

    Season fillets

    Generously coat both sides of each fillet with the blackening spice, pressing gently so the rub adheres.

  4. 4

    Cook fish

    Heat a large cast-iron skillet or heavy pan over medium-high heat until very hot (about 3–4 minutes). Add a thin film of oil if needed. Place fillets in the skillet and sear 3–4 minutes per side, depending on thickness, until a dark crust forms and the fish flakes easily with a fork (internal temperature 135–140°F / 57–60°C). If desired, add 1 tbs butter to the pan for the last minute and spoon the melted butter over the fillets.

  5. 5

    Rest fish

    Transfer cooked fillets to a plate and let rest 2–3 minutes while you prepare buns and sauce.

For the island tartar sauce

  1. 6

    In a medium bowl combine 1 cup mayonnaise, 2 tbs sweet pickle relish, 2 tbs finely chopped drained pineapple, 1 tsp minced red onion, 1 tbs lime juice, 1 tsp honey, 1 tbs chopped fresh cilantro, 1 tsp hot sauce, 1 tsp salt and 1/2 tsp black pepper. Stir until smooth. Taste and adjust seasoning — add more lime for brightness, honey to balance heat, or hot sauce for more kick. Refrigerate until ready to assemble (can be made up to 24 hours ahead).

For the sandwich assembly

  1. 7

    Prepare buns and produce

    Slice buns and spread the cut sides with butter. Toast in a skillet or under a broiler until golden, about 1–2 minutes. While toasting, wash and dry lettuce leaves, thinly slice tomato into 4 even rounds, and slice red onion if using.

  2. 8

    Assemble sandwiches

    Spread approximately 2 tbs of island tartar sauce on the bottom half of each toasted bun. Place 1–2 lettuce leaves on the sauce, add a blackened mahi mahi fillet, top with a tomato slice and a few red onion rings if desired. Spoon an additional 1 tbs tartar sauce on the top bun and close the sandwich.

  3. 9

    Serve

    Serve immediately with lemon wedges on the side for squeezing over the fish. Recommend pairing with fries, slaw or a light salad. Leftover sauce keeps refrigerated for up to 3 days.

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