‘Marinate’ the chicken in a bowl with the cornstarch and 1 teaspoon of rice wine/rice wine vinegar while you prepare the other ingredients.
Prepare the sauce by whisking together all of the ingredients in a medium-sized bowl, then set aside.
Heat up a wok or heavy-based wide pan with about a tablespoon of vegetable oil. Then stir fry the chicken pieces for a few minutes until they are just cooked. Take the chicken out of the pan, put it onto a plate and set aside.
Add a little more oil to the pan and stir fry the peppers, garlic, ginger and onion together for a few minutes on a high heat.
Add the chicken back into the pan along with the sauce and cook for a few more minutes until the sauce has thickened slightly and the chicken is cooked through.
At the last minute, add in the cashew nuts and spring onions/scallions. Give everything a final quick stir. Serve immediately with rice or noodles.
As with any stir-fry, I highly recommend preparing all the ingredients and whisking together the sauce before you start cooking. Then it's just a case of cooking the meat, taking it out of the pan, cooking the veggies, then tossing everything together with the sauce. Chicken breast or thighs? Your choice, honestly! I used to mostly make this with breasts, but these days I usually buy thighs because they're cheaper. Just trim the thighs to get rid of any excess fat.A note on the cashew nuts: I’d recommend only making as much of this as you need for one meal because the cashew nuts go a little soft when re-heated. Another option is to sprinkle the cashew nuts over each dish as you serve it so that if you have any leftovers your nuts will be safe.Alternatively, take the food that you think you aren't going to eat today out of the pan BEFORE adding the cashew nuts. This way you can reheat any leftovers without the cashews and stir them in afterwards so that they are nice and crisp.