Cut the chicken into 1 inch cubes and add to a bowl. Over the chicken add the soy sauce, rice vinegar, cornstarch, garlic powder and white pepper. Mix well and set aside.
Wash and chop your veggies.
Heat a large skillet or wok over medium-high heat and add the vegetable oil. When the oil is hot, add in the chicken so the bottom of the pan is covered but not overcrowded. You may have to cook it in two batches.
When the chicken is browned on all sides and cooked through, remove it to a plate lined with paper towel and repeat with the remaining chicken.
Measure out the sauce ingredients, mix them together well and set aside.
Clean your skillet or wok.
Add the sesame oil to the skillet or wok. Toast the cashews and remove to the plate with the chicken.
Add the peppers, white onions, spring onions, chilies and cook until they just begin to soften. Make sure the veggies are vibrant in colour and still have some crunch to them.
Add the chicken and cashews back in and mix. Add the sauce ingredients to the pan and mix them well until you get a nice, velvety sauce that thickens slightly.
Serve over rice or noodles.