• 12 scallions (green onions), trimmed to 150 mm (6-in) lengths
  • 500 gm  piece flank steak ,roughly 150 mm (6 in) square.
  • 60 ml (1/4 cup) sake 
  • 60 ml (1/4 cup) mirin 
  • 3 Tbsp light soy sauce
  • 1 Tbsp sugar
  • 1 Tbsp vegetable oil 
  • a meat pounder; kitchen string
  1. Blanch scallions in a pot of boiling salted water 45 seconds, then transfer immediately to a bowl of ice and cold water to stop cooking. Place scallions on paper towels to drain and pat dry. 
  2. Cut flank steak with the grain 3 mm (1/8 in) thick slices 40 to 50 mm (1½ to 2 in) wide. 
  3. Arrange slices 25 mm (1 in) apart on a very lightly oiled sheet of parchment paper or plastic wrap, then cover with another very lightly oiled sheet of parchment or plastic wrap (oiled side down) and pound slices with flat side of meat pounder until about  1.5 mm (1/16 in) thick.
  4. Arrange 3 beef slices side by side on a fresh sheet of plastic wrap, overlapping slices slightly to form a 150 mm (6 in) square with short ends of slices nearest you. Sprinkle square lightly with a pinch of salt, then lay 3 scallions (with some white parts at both ends) across slices at end closest to you and tightly roll up meat around scallions to form a log, using plastic wrap as an aid. Tie log with kitchen string at ends and where meat slices overlap. Make the rest  in the same manner.
  5. Stir together sake, mirin, soy sauce, and sugar in a small bowl until sugar is dissolved.
  6. Put rolls in a small baking dish and pour marinade over them, turning to coat. Marinate, loosely covered with plastic wrap, turning occasionally, 15 minutes.
  7. Heat a skillet over moderately high heat until hot,. 
  8. lift rolls out of marinade, letting excess drip off, and pat dry. (Save marinade.) 
  9. Add oil to skillet, swirling to coat bottom, then cook rolls, turning with tongs, until well browned on all sides, 4 to 5 minutes total for medium-rare. 
  10. Transfer rolls to cutting board. 
  11. Add remaining marinade to skillet and boil until slightly syrupy, 1 to 2 minutes, then remove from heat.
  12. Remove the  strings, then cut each roll crosswise into 6 slices. 
  13. Pour sauce into a shallow serving dish and arrange negimaki in sauce.