I'm trying to perfect my fish en papillote. I be recently made a cod (1in at 350 for 18min) and it was just overcooked and a salmon (1in at 450 for 18min) and it was perfect. I recognize I need an oven thermometer. once I have one, does anybody have a good resource for how long, how hot, which fish? I've been relying on a hodgepodge of recipes online & in books! thanks!