My take on Japanese beef yaki udon features a simple sweet and salty sauce loaded with black pepper and the steak gets a supporting cast of pak choi, onions and wonderful shiitake mushrooms.
If you are using dried udon noodles, cook them as per the instructions on the packet, then refresh them in cold water. If you are using straight-to-wok noodles, soak them in boiling water for a couple of minutes, gently separate them, then refresh them in cold water.
Slice the steak into thin strips (2-3mm or ⅛").
Top and tail the onion, cut it in half, peel it and then cut it into 5mm thick strips.
Cut the pak choi in half lengthways, chop off the root at the bottom, then cut the white parts into 1cm (just under ½") thick strips and the softer green parts into 2cm (just over ¾") strips.
Cut the stems off the shiitake mushrooms (you can freeze these; they make a wonderful stock), then cut the caps into 5mm (just under ½") thick strips.
Cut the spring onions into thin rounds at a 45-degree angle to the stem.
Peel the garlic cloves and slice them as finely as you can.
Peel the ginger and cut it into very thin batons.
Mix the ingredients for the sauce in a small bowl.
Heat a large wok over a fierce heat and when it is hot, add the cooking oil, followed by the beef strips, stir-fry them for 45-60 seconds. Remove them, leaving the oil in the wok.
Return the wok to the heat, toss in the onions and shiitake mushrooms and stir-fry for 2 minutes.
Toss in the garlic, ginger and pak choi, stir fry for 1 minute.
Add the noodles, beef and sauce to the wok, then stir fry for 1-2 minutes and serve garnished with the spring onions and sesame seeds.