Whisk all ingredients for the Hunan sauce in a bowl and set aside.
Combine the chopped chicken with the cornstarch and season with salt and pepper.
Heat the sesame oil in a non-stick pan over medium-high heat then add the chicken pieces. Stir fry for 2 minutes until almost done. Add the minced garlic and ginger, then sauté for 1 minute. Now, add the vegetables and stir fry for another 2 minutes.
Add the Hunan sauce and cook for 2 minutes.