Prepare the marinade. In a mixing bowl, combine olive oil, lemon juice, garlic, oregano, salt, and black pepper. Stir until everything is well blended.

Coat the chicken. Add the chicken breasts to the bowl and turn them until fully coated in the marinade. Cover and let sit for at least 15 minutes to absorb the flavors.

Preheat your cooking method. Set your air fryer to 400°F (200°C).

(Alternatively, preheat your oven or grill to the same temperature.)

Cook the chicken. Place the marinated chicken in the air fryer basket in a single layer. Cook for 25–30 minutes, turning halfway through, until: the outside is lightly golden the inside reaches 165°F (75°C)

Add the feta topping. During the last 5 minutes of cooking, sprinkle the feta cheese over the chicken. This allows it to soften slightly without fully melting.

Rest and garnish. Remove the chicken from the heat and let it rest for a few minutes. Finish with freshly chopped parsley before serving.