Almost any kind of fresh fish can be baked including salmon, cod, tilapia, halibut, and trout. Fish can be baked in a very hot oven or a very slow oven. Some recipes instruct placing a fillet of fish on an ovenproof plate and baking it at only 200 degrees. The best way to test whether fish is cooked all the way through, is to pierce it with a knife. If the knife is hot, so is the fish.