A bain-marie is a kitchen appliance used for gentle heating and maintaining the temperature of food. It consists of a large outer container that holds hot water, and smaller inner pans or containers where food is placed. This product is commonly used in buffets, catering, or commercial kitchens to keep soups, sauces, and other prepared dishes warm without overcooking or drying out the food. It's ideal for holding delicate dishes at a consistent temperature for long periods.