Rinse the chicken breasts, pat dry, then butterfly and cut in half. You will have 6 pieces. Set aside.

In a shallow bowl, whisk together flour, 2 teaspoons buttermilk powder, and salt. Set aside.

In another shallow bowl, whisk together egg, melted butter, and Worcestershire sauce.

In a third shallow bowl, stir together breadcrumbs, Parmesan cheese, remaining 1 teaspoon dried buttermilk powder, Old Bay seasoning, paprika, garlic powder, dry mustard and pepper.

Working with one chicken piece at a time, dredge all sides in flour mixture, shaking off excess. Next, dip in butter mixture, coating all sides and letting excess drip off. Next, coat all sides with breadcrumb mixture, pressing down to make sure the crumbs stick to the chicken. Place breaded chicken on a large cookie sheet. Repeat process with the remaining chicken pieces, placing in a single layer on the cookie sheet.

Refrigerate breaded chicken for at least 25 minutes.

Preheat air fryer to 390 degrees.

Spray air fryer basket with nonstick cooking spray. Arrange breaded chicken pieces in a single layer (you may need to cook chicken in batches, depending on the size of the breasts and of your air fryer). Cook for 5 minutes. (See Note below on cook times.)

Carefully turn over and continue cooking for an additional 3 minutes or until internal temperature reaches 165 degrees on an instant-read thermometer.

Remove from fryer, place on a wire rack, and let rest at room temperature for 5 minutes before serving.