To make the sauce, put all the ingredients in a saucepan and simmer gently until syrupy, so around 3-4 mins. Take off the heat and set aside.
Season the chicken wings with salt, pepper and the grated ginger. Toss the chicken with the cornflour until completely coated.
Heat about 2cm of vegetable oil in a large frying pan over a medium/high heat. Fry the chicken wings for 8-10 mins until crisp, turning halfway. Remove from the oil and place on kitchen paper. Leave to cool slightly (around 2 mins).
Reheat the sauce, and toss the crispy chicken wings in it. Tip into a bowl and top with the sesame seeds and sliced spring onions.