A steamer accessory for steam-heating and/or steam-cooking food contained in a container carrying the steamer accessory, includes a steam generator including a steam production chamber connected to at least one steam distribution outlet provided in a lower part of the steam generator, the steamer accessory including a bearing surface intended to rest on the container. The bearing surface has an indentation providing a vent capable of bringing the inside of the container into communication with the outside of the container when the container is carrying the steamer accessory.