Defrost Cod Fillets.
Heat oven to 425 F.
Line a rimmed baking sheet with aluminum foil or parchment paper, then spray with nonstick cooking spray or grease with oil.
Sprinkle both sides of the defrosted fish pieces with salt and freshly ground black pepper.
In a wide bowl, combine the panko crumbs and the parsley.
In another bowl, whisk the eggs with the Cajun seasonings and mayonnaise.
Dip the fish fillets in the plain flour, coating each piece thoroughly.
Dip the flour-coated fillets in the egg mixture, then coat with the panko crumb mixture, pressing lightly to help crumbs adhere to the fish. Repeat with the remaining fillets.
Arrange the crumb-coated fish on the prepared baking sheet.
Bake for about 16 to 20 minutes, or until the fish flakes easily with a fork. The time in the oven depends on thickness, so adjust for very thin or very thick fish fillets.
Meanwhile, cut the lemon into four wedges.
Serve the baked fish fillets with the lemon wedges and tartar sauce or remoulade sauce