A bain-marie, also known as a water bath or double boiler, is a piece of equipment used in science, industry, and cooking to heat materials gently or to keep materials warm over a period of time. In cooking, a bain-marie usually consists of a pan of water in which another container or containers of food to be cooked is/are placed. The purpose of a bain-marie is to create a gentle heat around the food and result in a uniform cooking process. There are a few culinary setups that can more or less correctly be referred to as a bain-marie. In every case, the process involves using a container of hot water to deliver indirect heat, or steam, or both to the food.
Bain-maries can come in any number of shapes and sizes, but in common restaurant uses, they are made from stainless steel, which is a good conductor of heat and easy to clean and maintain. Bain-maries can be used to melt ingredients for cooking, such as chocolate, to avoid splitting and caking onto the pot. They can also be used to keep food warm over time. Cheesecake is often baked in a bain-marie to prevent cracking and ensure even cooking.
To create a bain-marie, a container of hot water is used to deliver indirect heat, or steam, or both to the food. Another setup that sometimes goes by the name of bain-marie is really a double boiler. A double boiler is a cooking tool that includes a pot of hot water simmering on the stovetop, and then a bowl or insert situated above the pot of boiling water. Usually, a double boiler is used for transmitting gentle heat, like when melting chocolate or making hollandaise sauce.
