How to Make It
Combine first 3 ingredients in a large bowl; stir until salt dissolves. Add chicken; submerge to fully coat with buttermilk mixture. Cover bowl. Refrigerate 8 hours (or at least 2 hours and up to 24 hours).
Preheat oven to 400°F.
Place a wire rack on a baking sheet; coat rack with cooking spray. Combine panko and remaining ingredients in a large bowl; stir well. Remove chicken from marinade, one piece at a time, letting excess drip off; dredge in panko mixture to coat. Place coated chicken on prepared rack. Repeat with remaining chicken and panko mixture. Spray coated chicken with cooking spray. Place chicken in oven; bake at 400°F for 30 minutes or until browned and meat is done. Let stand 10 minutes; serve.