By Harold McGee
Oven baking is a versatile method for cooking fish. Because it transfers heat to the fish mainly by hot air, which is an inefficient method, it’s relatively slow and gentle, and makes it easier to avoid overcooking. This is true as long as the container remains open to the oven air, when the fish moisture evaporates and cools the surface to well below the thermostat temperature. If the container is closed, water vapor builds up inside and the fish quickly steams rather than bakes. The dry oven air is also useful for concentrating the fish juices and any moist flavoring ingredients—wine, or a bed of aromatic vegetables, for example—and it can also trigger aroma-producing browning reactions.