Combine sauce ingredients and set aside.
In a bowl, combine cornstarch, sugar and salt. Add chicken and toss.
Heat wok or frying pan to highest heat. Add oil. Heat to hot, not smoking.
Add chicken, ginger, garlic and onion. Stir until chicken is opaque (about 1 minute).
Add peppers and carrots. Stir 2-3 minutes.
Add peas and sauce. Cook until sauce comes to a boil.
Add cashews and sprinkle with sesame seeds.
Serve immediately.