Wash the mushrooms and soak them in 1/8 litre water. Dab meat dry and cut into thin strips. Add 4 tablespoons of Teriyaki sauce and wasabi, mix and leave to soak for approx. 20 minutes.
Clean, wash and cut the peppers into strips. Clean, wash and halve the pak-choi. Prepare noodles in boiling salted water according to package instructions. Drain mushrooms, collect soaking water. Halve mushrooms.
Heat 2 tablespoons of oil in a wok. Fry the meat in it in portions while turning, remove. Season with salt. Add 2 tablespoons of oil to the frying fat and heat. Fry the peppers for approx. 3 minutes. Add pak choi and mushrooms and fry for another 2 minutes.
Add mushroom water and bring to the boil. Add meat again. Season to taste with 2 tablespoons of Teriyaki sauce. Wash coriander, dab dry, remove leaves and add to meat. Drain noodles. Arrange beef shredded with the noodles on a plate.