Beef teriyaki fusion style!

Ingredients; big mushrooms 8, spring onions 8, potatoes 6, rump-steak 4 (100 gr each), salt, dark soy sauce 3 tbsp, mirin 3 tbsp, rice wine 3 tbsp, teriyaki sauce 1 tbsp, garlic 2 cloves, fresh ginger 2 cm, sunflower oil 4 tbsp

Boil the potatoes in salted water until done.
Mix the soy sauce, mirin, rice wine and teriyaki sauce in a cup. Add sliced ginger and finely cut garlic.
Make a cross like incision on top of the mushrooms. chop the spring onions in to 5 cm pieces. Cut the boiled potatoes in quarters.
Heat a wok and add 2 tbsp of oil. Add the mushrooms and fry for about 5 minutes. Stir constantly and add a splash of water if necessary. Put the mushrooms in a bowl. Fry the spring onion for 1 min., and put them in the bowl. Fry the potatoes for 2 to 3 minutes and add them to the bowl.
Make sure the wok is very hot, and add 2 tbsp oil. Fry the rump-steak 1 min. each side. Fry them one at the time. Put aside. Add the bowl of vegetables to the wok, add the sauce mixture. Once it is cooking add the steak. Cook for to more minutes.
If the sauce is to thin for your liking; mix a tsp of potato flower with 2 tbsp of water. Add to the cooking food while mixing well for 1 minute.