Pat the chicken pieces completely dry with paper towels. Season them all over with 1 teaspoon of kosher salt and 1 teaspoon of black pepper. Place the seasoned chicken in a large bowl or a resealable plastic bag and pour the buttermilk over it, ensuring every piece is coated. Cover the bowl or seal the bag and refrigerate for at least 1 hour, or preferably overnight for the most tender and flavorful results.
In a wide, shallow dish (like a pie plate), whisk together the all-purpose flour, seasoned salt, garlic powder, paprika, and the remaining 1 teaspoon of salt and pepper. Mix until the seasonings are evenly distributed.
Set up a breading station with your marinated chicken and the dish of seasoned flour. One piece at a time, remove the chicken from the buttermilk, allowing any excess to drip off. You want a thin layer of buttermilk remaining to help the flour stick. Dredge the chicken in the flour mixture, turning to coat all sides and pressing gently to ensure a thick, even coating. Shake off any excess flour and place the coated piece on a wire rack. Let the chicken rest on the rack for about 10-15 minutes to help the coating set.
Preheat your air fryer to 375°F (190°C) for about 5 minutes. Preheating is crucial for a crispy crust.
Lightly spray the inside of the air fryer basket with oil. Arrange the chicken pieces in a single layer, making sure not to overcrowd the basket. Work in batches if necessary. Generously spray the tops of the chicken pieces with oil until no dry flour is visible. Air fry for 15 minutes.Using tongs, carefully flip each piece of chicken. Spray the other side with oil. Continue to air fry for another 10-15 minutes, or until the chicken is golden brown, crispy, and cooked through. The internal temperature should register 165°F (75°C) on a meat thermometer inserted into the thickest part without touching the bone. Remove the chicken from the air fryer and let it rest on a wire rack for 5-10 minutes. This allows the juices to redistribute, ensuring every bite is moist. Serve hot with your favorite sides.