Jul 13 2026
RestaurantsThe Original Roy's in Hawaii KaiRoy Yamaguchi’s Blackened Island Ahi Recipe

Roy Yamaguchi’s Blackened Island Ahi Recipe

Time45m
Serves4

Spicy Soy Mustard, Butter Sauce, Nori Puree, Cucumber Namasu

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Ingredients

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Ahi Preparation

Spicy Soy Mustard Sauce

Butter Sauce

Nori Puree

Cucumber Namasu

Method

Ahi Preparation

  1. 1

    Season Ahi

    Rub the Ahi tuna steaks with Cajun seasoning evenly on all sides.

  2. 2

    Heat Oil

    In a skillet over medium-high heat, add vegetable oil and heat until shimmering.

  3. 3

    Cook Ahi

    Sear the Ahi steaks in the hot skillet for about 2-3 minutes on each side, or until blackened and cooked to your desired doneness. Remove and set aside.

Spicy Soy Mustard Sauce

  1. 4

    Mix Sauce

    In a small bowl, whisk together soy sauce, Dijon mustard, Sriracha, and honey until well combined. Set aside.

Butter Sauce

  1. 5

    Prepare Butter Sauce

    In a small saucepan over medium heat, melt the butter and add minced garlic. Sauté until fragrant, about 1 minute. Remove from heat and stir in lemon juice.

Nori Puree

  1. 6

    Prepare Nori Puree

    In a blender, combine nori sheets and water. Blend until smooth. Strain if necessary.

Cucumber Namasu

  1. 7

    Prepare Namasu

    In a bowl, combine thinly sliced cucumber, rice vinegar, sugar, and salt. Toss and let it marinate for at least 15 minutes.

Plating

  1. 8

    Serve

    On a plate, place a portion of the blackened Ahi, drizzle with Spicy Soy Mustard Sauce, and Butter Sauce. Add a dollop of Nori Puree and serve with Cucumber Namasu on the side.

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