Ingredients

  • 2 bunches scallions, white and tender green parts only
  • 1/2 pound shiitake, stems discarded
  • Kosher salt and coarse black pepper
  • 1 pound sirloin steak, 1 1/4 inches thick
  • Three 8-inch-square sheets of nori (dried seaweed), torn into small pieces
  • 1 tablespoon sesame seeds
  • 1 teaspoon crushed red pepper
  • 1 1/2 tablespoons extra-virgin olive oil
  • 2 tablespoons tamari or soy sauce
  • 1 tablespoon mirin
  • 1 1/2 teaspoons fresh lemon juice
  • 2 tablespoons wasabi powder mixed with 2 tablespoons water

Method

  • Preheat the oven to 400.
  • In a small saucepan of boiling water, blanch the scallions for 2 minutes.
  • Drain and rinse under cold water.
  • Set a rack on a baking sheet and arrange the shiitake caps on the rack, gill sides down.
  • Season lightly with salt and pepper.
  • Season the steak with salt.
  • In a food processor, coarsely grind the nori with the sesame seeds, red pepper and 1 teaspoon black pepper.
  • Spread the nori mixture on a plate and dredge the steak in it.
  • In a medium skillet, heat 1 tablespoon of the olive oil until shimmering.
  • Add the steak and cook over moderately high heat until the nori is toasted, about 4 minutes per side.
  • Place the steak over the mushrooms and roast for about 15 minutes, or until an instant-read thermometer inserted in the center of the meat registers 130 for medium rare.
  • Transfer the steak to a cutting board and let rest for 10 minutes.
  • Meanwhile, halve the scallions lengthwise and quarter the mushroom caps.
  • In a small bowl, whisk the tamari with the mirin, lemon juice and the remaining 1/2 tablespoon of olive oil.
  • Slice the steak 1/4 inch thick and arrange it on plates with the shiitake mushrooms and scallions and a small mound of wasabi.
  • Drizzle the tamari sauce over the steak and serve.