Heat the oil in a large frying pan or wok over high heat. Add the chicken and stir-fry for 4–5 minutes, until browned and almost cooked through.
Add the onion, capsicums and beans. Stir-fry for 3–4 minutes, until just tender. Add the garlic and cook for 1 minute more.
Pour in the Mala sauce along with the water and toss to coat the chicken and vegetables in the sauce. Stir-fry for 2–3 minutes, until the chicken is cooked through and the sauce is bubbling.
Serve with rice alongside, sprinkle with peanuts and spring onions.