Ingredients
1 tbsp wok oil (or flavourless oil) 
1 small onion, sliced 
2 cloves of garlic, finely chopped 
½ tbsp finely chopped ginger 
¼ cabbage, sliced 
4 sliced mushrooms, ideally oriental varieties such as shitake and wood ear but in reality any will work 
¼ tin of drained water chestnuts * 
¼ tin of drained bamboo shoots * 
Wok ready udon noodles (or any wok ready noodles if you cannot find udon), opened and separated 
2 tbsps water 
½ tsp sesame oil 
1 tbsp soy sauce 
2 tbsp sweet soy sauce (or ketjap manis) 
1 tbsp mirin 
½ tsp shichimi togarashi or red pepper flakes 
Salt 

Method
Get everything prepared beforehand because once you start to cook it will be fast and you won't have time to stop and chip as you don't want to burn anything. 

Mix the sesame oil, soy sauce, sweet soy sauce, mirin and shichimi togarashi together in a small bowl and put to one side. 

Over a fairly high heat, heat your oil in a wok and add your onions and cook for 3-5 minutes until soft.  Add the garlic and ginger and cook for a further minute.  Add the cabbage, mushrooms, water chestnuts and bamboo shoots and cook for a further 2-3 minutes.  If your wok starts to smoke add a tbsp of either water or oil and stir. 

Add 2 tbsps of water and then add the separated noodles and mix. Cook until the water evaporates and then add the sauce and turn off the heat.  Give everything a thoroughly good mix, check you are happy with the seasoning and serve.