Pound the chicken breasts until they are about 1/4 inch thick.
Season each breast with salt and pepper, ensuring even coverage on both sides.
In a bowl, mix buttermilk and eggs until well combined.
Place the chicken in the buttermilk mixture and let it marinate for 5-6 hours in the refrigerator.
In another bowl, combine flour, garlic powder, onion powder, and cayenne pepper.
Remove chicken from the marinade and coat it in the flour mixture.
Dip the chicken into melted butter, then coat it with panko breadcrumbs.
Bake at 375°F for 40 minutes, or until crispy and golden brown.