If needed per your air fryer model, preheat the air fryer to 380 degrees F.
In a small bowl, combine the salt, paprika, pepper, garlic powder, onion powder, cayenne pepper, and brown sugar.
Trim the chicken breasts of any fat or grizzle. Place between 2 sheets of plastic wrap and use a meat mallet to pound the chicken out until it is even in thickness.
If not using cooking spray, brush the chicken breasts with oil. Sprinkle with the spice rub and rub into the chicken breasts. Flip the chicken and repeat on the other side.
If you did not brush the chicken with oil, spray lightly with cooking spray and place the chicken breasts, sprayed side down in basket or on rack in the air fryer. Spray the opposite side of the chicken with cooking spray as well.
Air fry the chicken for 6 minutes at 380 degrees F. Remove the basket and flip the chicken and air fry for another 6 minutes, or until the chicken reaches an internal temperature of between 162 to 165 degrees F.
Immediately remove the chicken from the air fryer and place it on a platter or cutting board, loosely tent with foil, and let rest for 5 minutes before slicing and serving.
Chicken: Use chicken breasts or chicken thighs that are between 6-8 ounces each. Any larger would require longer cook time.Temperature of Chicken: Chicken needs to reach 165 degrees F to be safe to eat. If your chicken is not 162-165 degrees after air frying as directed, continuing cooking in 1-2 minute intervals. Keep in mind it will rise a few degrees while resting. Leftover chicken can be stored in an airtight container for 3 days in the refrigerator. Leftovers can be reheated in the air fryer for 2-3 minutes at 380 degree F or served cold.Seasonings: Feel free to omit the sugar or salt if needed/desired for dietary concerns. You can also use regular paprika in place of smoked paprika, or for a less smokey flavor. You can also use your favorite spice rub or blend in place of the homemade blend.Doubling the Recipe: To double this recipe, you may need to work in batches, if your air fryer is small. Double the dry rub and work in batches to air fry the chicken. Keep the first batch in the oven at 200 degrees F while the other batch cooks up.