First, cut the chicken breasts into thin strips and place them in a bowl. Next, add the olive oil, salt, black pepper, cumin, chili powder, and cayenne pepper (if using) to the bowl and mix well to coat the chicken evenly with the spice mixture.

Preheat your air fryer to 375 degrees Fahrenheit and lightly coat the basket with cooking spray. Place the chicken strips in a single layer in the basket, making sure they are not touching.

Cook the chicken jerky in the air fryer for about 20-25 minutes, or until it is cooked through and crispy. You may need to cook the chicken in batches, depending on the size of your air fryer.

Once the chicken is cooked, remove it from the air fryer and let it cool on a wire rack. The chicken jerky will become more crispy as it cools. Enjoy your spicy chicken jerky as a tasty and satisfying snack.