Cut the chicken into 1-inch pieces. Set aside.
In a large bowl, whisk the egg. Stir in the chicken chunks until well coated. Place the chicken pieces on a plate lined with a paper towel to remove the excess egg.
Place ½ cup cornstarch, salt, and pepper in a large Ziploc bag.
Add the chicken pieces to the bag and shake until they are evenly coated. Set aside.
Spray the air fryer basket with oil spray.
Place the chicken into the air fryer in one even layer then spray the chicken with oil spray.
Cook the chicken at 400°F for 6 minutes. Shake the basket to loosen and turn the chicken, then continue to cook for another 6 minutes.
While the chicken is cooking, start the sauce.
In a medium saucepan over medium heat, add orange juice, granulated sugar, white vinegar, soy sauce, honey, garlic powder, ginger, and a pinch of red chili flakes (optional). Stir often and bring to a simmer.
In a small bowl, mix the remaining cornstarch and water. Add this mixture to the sauce and simmer for another 5-10 minutes, or until it reaches the desired thickness.
Add the cooked chicken to the sauce and stir to coat.
