In a bowl, combine the olive oil, lime juice, minced garlic, ground cumin, chili powder, paprika, dried oregano, salt, black pepper, and cayenne pepper (if using). Mix the ingredients thoroughly until well combined.

Place the boneless, skinless chicken breasts in a shallow dish or a resealable plastic bag.

Pour the marinade over the chicken, making sure to coat each piece evenly. Seal the bag or cover the dish and refrigerate for at least 30 minutes to allow the flavors to infuse into the chicken. For even better results, marinate the chicken for a few hours or overnight.

Preheat your air fryer to 400°F (200°C) for a few minutes. Preheating ensures that the air fryer reaches the desired cooking temperature, resulting in evenly cooked chicken.

Lightly grease the air fryer basket with cooking spray or brush it with a thin layer of olive oil. This will prevent the chicken from sticking to the basket.

Once the chicken has marinated, remove it from the refrigerator and let it sit at room temperature for a few minutes.

Place the marinated chicken breasts in a single layer in the air fryer basket, ensuring they are not overcrowded. You may need to cook them in batches if your air fryer is not large enough to fit both chicken breasts comfortably.

Air fry the chicken at 400°F (200°C) for 12-15 minutes, flipping the chicken halfway through the cooking process. The chicken is done when its internal temperature reaches 165°F (74°C), and it is cooked through and nicely charred.

Once done, remove the air-fried chicken from the basket and let it rest for a couple of minutes before slicing or serving. This resting period allows the juices to redistribute, ensuring the chicken remains tender and juicy.