DRESSING (whisk together):
1Cook noodles following packet instructions. Rinse under cold water and drain well.
2Meanwhile, rub ginger over tuna. Roll tuna in sesame seeds and season with salt.
3Heat oil in a large frying pan or char-grill pan over medium fire. Sear tuna 1 to 2 mins on each side, or until cooked to taste. Set aside, loosely covered with foil, for 5 mins. Using a sharp knife, cut into thin slices.
4When ready to serve, pour dressing over noodles. Add sprouts, orange segments and spring onions, tossing to combine. Serve noodles topped with tuna slices.
Photo: Bauer/Rob Shaw