Preheat broiler. Lightly brush broiler pan rack with olive oil spray.
Brush or rub the skin-side down, on the broiler rack.
Season the top with salt, pepper, Cajun seasoning, and drizzle a little more olive oil.
Place the fillets under the broiler, about 5 to 6 inches from the heat, and broil until the fish is done or starts to flake, about 10 minutes.
Serve immediately, with creamy shrimp sauce or salsa.
Serves 2 to 4.