Marinate the chicken with Shaoxing wine for 20-30 minutes.
Bring a saucepan of water to the boil, put in the ginger and spring onion, and then the chicken fillets.
Simmer without the lid on for 15 - 20 mins until it's cooked.
Meanwhile, make the sauce by combining sugar and vinegar, and then tip in all the rest of the sauce ingredients, mix until incorporated.
Fish the chicken out, left to cool and reserve the cooking liquid! You've got yourself a bowl of oriental flavour stock.
When cooled, cut the chicken into long stripes, and cut the cucumber into long stripes too. (You can put the chicken and cucumber away in the fridge now, if you're making ahead)
To assemble the dish, arrange the chicken on a plate, topped with cucumber and drizzle the sauce over.
Serve cold and enjoy!