Prepare the Chicken. Cut the boneless, skinless chicken thighs into bite-sized pieces and season with salt and pepper.
Coat with Cornstarch. In a bowl, toss the chicken pieces with cornstarch until evenly coated. This will help create a crispy coating when air-fried.
Air Fry the Chicken. Preheat your air fryer to 400°F. Place the coated chicken pieces in a single layer in the air fryer basket, making sure they are not touching. Cook for 10-12 minutes, flipping halfway through, until golden brown and crispy.
Make the Orange Sauce. In a saucepan, combine orange juice, soy sauce, red pepper flakes, honey, grated ginger, minced garlic, and a pinch of red pepper flakes. Bring the mixture to a simmer over medium heat and cook until slightly thickened.
Coat the Chicken. Once the chicken is cooked, transfer it to a bowl and pour the orange sauce over the top. Toss until the chicken is evenly coated in the sauce.
Garnish and Serve. Sprinkle toasted sesame seeds over the chicken for added flavor and crunch. Serve the Air Fryer Orange Chicken hot, garnished with sliced green onions and a wedge of fresh orange.