In a bowl, mix buttermilk, salt, pepper, garlic powder, and paprika.
Add chicken tenderloins and marinate for 20–30 minutes.
In another bowl, mix flour, panko, and all seasoning ingredients.
Remove chicken from marinade and let excess drip off.
Coat each piece in breading mixture, pressing lightly to stick.
Preheat air fryer to 380°F (193°C).
Spray basket lightly with cooking spray.
Place chicken in a single layer (do not overcrowd).
Air fry for 10–12 minutes, flipping halfway through.
Cook until golden and internal temp reaches 165°F (74°C).
Rest for 2–3 minutes and serve.