Marinate the chicken: Pat chicken dry. In a bowl, whisk buttermilk, hot sauce, and salt. Add chicken and toss to coat. Cover and chill at least 1 hour, up to 12 hours. Short on time? Even 30 minutes helps.

Mix the coating: In a shallow dish, combine flour, cornstarch, salt, paprika, garlic powder, onion powder, thyme, oregano, black pepper, white pepper, and cayenne. Stir well so the flavor is even throughout.

Set up dredging station: Beat the egg in a small bowl (if using). Remove chicken from buttermilk, letting excess drip off. If skipping the egg, keep the buttermilk as your wet layer.

Dredge for crunch: Dip each piece in egg (or straight from buttermilk), then into the flour mixture. Press the coating firmly to create a thick, even crust. Place coated chicken on a plate or wire rack for 5–10 minutes to help it set.

Preheat the air fryer: Heat to 375°F (190°C) for 3–5 minutes. A hot basket helps start the crisping right away.

Oil the basket and chicken: Lightly spray the air fryer basket with cooking spray. Arrange the chicken in a single layer with space between pieces. Lightly mist the tops with cooking spray, or brush with a small amount of oil to prevent floury spots.

Air fry, then flip: Cook at 375°F for 12 minutes. Flip the chicken, spray again, and cook another 10–14 minutes. Dark meat usually needs 22–26 minutes total; bone-in breasts may need a little longer.

Check doneness: Use an instant-read thermometer in the thickest part (not touching bone). You want 165°F for white meat and 175–185°F for dark meat for the best texture. If needed, cook in 2–4 minute bursts until done.

Rest for crunch: Let the chicken rest on a wire rack 5 minutes. This keeps the bottom from steaming and softening the crust.

Serve: Sprinkle with a pinch of salt if needed. Enjoy hot with coleslaw, biscuits, or corn on the cob.