A bain-marie (French for water bath) is a simple technique used for baking delicate dishes like custards, cheesecakes, mousses and terrines. It works to prevent cracking or curdling by surrounding the food being baked with hot water to produce an even, gentle heat.
Making and Using A Bain Marie or Water Bath
To make a bain-marie, choose an outer container that is deep enough to hold water at least 1/2 to 2/3 the depth of your ramekins, souffle dish, etc. and large enough to allow for at least 1/2-inch between the individual containers.
You can line the outer container with a kitchen towel to keep the inner dishes from sliding in the pan if desired, but it's not required.
Slowly pour boiling water into the outer container, move it carefully to the oven and bake your recipe according to instructions.
Be sure to remove your food from the bain-marie as soon as it's done, because if left in the hot water, it will continue to cook, even once it's out of the oven.