If any of your chicken breast fillets are thick, slice them lengthwise to make evenly sized pieces for consistent cooking.
Season the chicken generously with salt, black pepper, and garlic powder on all sides.
Set up three separate bowls: one with all-purpose flour, one with the beaten egg, and one with panko breadcrumbs.
Dredge each piece of chicken first in the flour, shaking off any excess, then dip into the beaten egg, and finally coat thoroughly in the panko breadcrumbs.