Combine chicken with marinade ingredients. Mix well, cover and set aside for 15 minutes.
In a large skillet or non-stick frying pan, saute chicken with 1 tablespoon of oil on high heat. Turning every minute for about 4 minutes or until chicken is caramelised but not cooked through. (note 2) Transfer to a bowl and set aside.
In the same pan (without washing), add remaining 1 tablespoon of oil, onions, garlic and capsicums (bell peppers). Cook on high heat until vegetables slightly charred and caramelised (flavour!). About 4 minutes.
Whilst vegetables are cooking, combine all the sauce ingredients in a small bowl and mix well until sauce is smooth and constarch is disolved.
Add cashew nuts and chicken back into the pan, mix through then pour in prepared sauce. Reduce heat down to medium and stir until sauce thickens and chicken is cooked. This should take about 2 minutes.
Serve with freshly steamed rice!