Pat the chicken breasts dry with paper towels to remove surface moisture.
If very thick, butterfly or pound to even thickness (about 1/2–3/4 inch).
Rub each breast with olive oil to help seasoning adhere and promote browning.
Mix salt, pepper, garlic powder, onion powder, paprika, and oregano in a small bowl.
Generously season both sides of each breast with the spice mix; add lemon zest or juice if using.
Preheat the air fryer to 375°F (190°C) for 3 minutes for even cooking.
Place breasts in the basket single layer with space between; do not overcrowd.
Cook at 375°F (190°C) for 10–12 minutes, then flip once and continue 2–4 more minutes.
Check internal temperature with a probe thermometer — aim for 160–165°F (71–74°C).
Let rest 5–7 minutes tented with foil; carryover heat brings the center to perfect doneness.