bain-marie [beyn-muh–ree; French ban-ma-ree] noun
The French term for water bath or double-boiler. Some companies make a bain-marie set featuring a bottom pot, where water is placed, and a top pot that fits snugly into the base. The bottom of the top pot extends down into the bottom pot. These sets usually include a lid as well.
For extremely gentle cooking, place the food in the top of the bain-marie over simmering water. It is often recommended for recipes such as pastry creams and lemon curd, among others. Many professional chefs and home cooks create their own bain-marie by using a heatproof bowl that fits down into a pot.