Place 2 chicken breasts on a cutting board. Cut them in half, width-wise so that you have four thin chicken cutlets.
Place a piece of plastic wrap over all of the chicken pieces on the cutting board. Use a meat mallet to pound the chicken until they are about ¼ - ½” thick.
Remove the plastic wrap. Then sprinkle both sides of the chicken with salt and freshly-cracked black pepper.
Get out 3 separate shallow bowls (I sometimes use cake pans or pie tins) and pour 1 cup flour in one, the 2 beaten eggs in another, and 2 cups panko breadcrumbs in the final pan.
Pick up one of the chicken pieces and first dip it in the all purpose flour, making sure it is evenly coated on both sides.
Next, rub the chicken in the beaten egg, making sure it is evenly coated on both sides.
Finally, dip the floured and egged chicken in the panko breadcrumbs. Press the chicken into the breadcrumbs so that the breadcrumbs stick and the chicken is evenly coated. Make sure there is no surface area without breadcrumbs.
Repeat this process with as many chicken pieces as can fit in your air fryer at once. I have a mini air fryer that can only fit one piece of chicken, so I only prepared one piece of chicken at a time.
Place the chicken in a single layer in your air fryer basket. Spray the top of the chicken with nonstick spray. Cook for 8 minutes on the first side.
When the 8 minutes are up, turn the chicken over and spray the other side with nonstick spray. Continue cooking for another 6-8 minutes until both sides of the chicken are brown and the interior of the chicken is cooked through.
Repeat steps 5-10 until all of the chicken katsu is cooked. Enjoy!