Place chicken pieces in a large bowl or zip-top bag with buttermilk. Refrigerate for at least 2 hours, preferably overnight, to tenderize and keep juicy.

In a shallow dish, combine flour, breadcrumbs, cornstarch, salt, pepper, garlic powder, paprika, and onion powder.

Remove chicken from the buttermilk, letting excess drip off. Dip each piece into the beaten eggs, then coat thoroughly in the seasoned flour-breadcrumb mixture.

Preheat air fryer to 375°F (190°C). Arrange chicken in a single layer in the basket (work in batches if needed). Lightly spray with cooking spray or brush with oil.

Air fry for 25–30 minutes, flipping halfway through, until golden brown and the internal temperature reaches 165°F (74°C).

Let chicken rest for 3–5 minutes before serving so the juices redistribute.