In a food processor, combine chicken breasts, panko, chopped onion, egg, cornstarch, garlic powder, salt, and pepper. Blend until smooth.
Using a 1 tablespoon cookie scooper, scoop the chicken mixture and use your hands to form into chicken nugget. If your hands are sticky, grease them with avocado oil.
Once you have formed chicken nuggets, place them into air fryer at 380°F for 10 minutes and then flip them over and cook for an additional 5 minutes or until golden brown. Enjoy with your favorite dipping sauce!