Marinate the chicken with cornflour, salt, chilli oil, Sichuan pepper and refrigerate for at least 2 hours.
Heat oil in a pan and shallow fry the chicken pieces; drain and keep aside.
Remove excess oil and roast the cashewnuts in the same pan and keep aside.
In the same pan (add more oil if necessary), sauté garlic and ginger for a minute. Add dry red chillies and sauté for one more minute on low heat.
Add chilli garlic sauce, cooking wine, sugar and mix well.
Add the chicken pieces and cashews; mix to combine.
Remove from heat and garnish with spring onions.