Season the fillets to taste with the salt, lemon pepper and garlic powder. In a small bowl, stir together the brown sugar, soy sauce, water and oil until sugar is dissolved.
Preheat oven to 450 degrees Fahrenheit. Line a broiler pan with aluminum foil and make a few slits through the foil with a knife to allow juices to drain while cooking.
Place your fillets on the broiler pan and discard the leftover marinade. Place the fillets into your preheated 450 degree oven for 15 minutes.