Slice into individual portions. Season with salt and pepper. Place in foil or parchment paper lightly oiled and lined with lemon(to make a "tent"). Add some finely julienned vegetables (carrots, fennel, peppers, whatever you like), drizzle with a little olive oil, chili flakes if you prefer, a splash of wine and a small knob of butter. Create "tent" and bake in the oven for about 10 minutes.
I serve this with some quinoa, grilled asparagus and a mango salsa.
Alternately, you can buy some miso, combine with grated garlic and ginger, a little soy sauce, some sugar, mirin (Japanese cooking wine), and some sake, and rub onto the fish and let marinate overnight. Then bake in the oven and you then get a Nobu-style miso salmon (instead of cod).