Mix all the sauce ingredients in a small bowl and set aside for later.
Heat a wok on medium and add 2 tsp cooking oil. Add 3 tbsp dried baby shrimp (hoshi ebi) and 2 tbsp Japanese leek (naganegi) and fry for 1 minute to flavour the oil.
Turn up the heat to medium high and add 200 g shrimp and 100 g asparagus , fry until the shrimps are cooked through. (2-3 minutes)
Add 100 g bean sprouts and 50 g green cabbage and fry for 1-2 minutes.
Push all the ingredients to one side and add 2 portions udon noodles.
Heat the noodles through until they come apart easily and then pour the shio lemon sauce into the wok. Stir fry everything together for 1-2 minutes.
Dish up and sprinkle with 2 tbsp finely chopped green onions.