To make the stir-fry sauce, combine the ingredients together in a small bowl. Set aside.
Season the chicken with salt, pepper and toss with the corn flour.
Fill a frying pan with 1/2 cup oil and heat over high heat.
Shake off the excess flour from the chicken and add to the hot oil.
Cook and keep flipping the pieces until the chicken is golden.
Transfer to a tray lined with paper to drain.
Heat 1 tablespoon of oil in a frying pan over medium-high heat.
Add the onion and fry for 30 seconds.
Add the dried chilies, garlic and ginger and fry for another 30 seconds.
Mix in the cashews and fry for another minute.
Add the capsicums and stir-fry for another minute or 2.
Add the chicken and the sauce. Cook for a few minutes and garnish with spring onion.