A couscoussier is a traditional double-chambered food steamer used in Berber cuisine (particularly Moroccan and Tunisian) to cook Couscous.[1]
It is typically made of two interlocking metal pots. The first, larger pot, holds water used to make steam. The smaller pot, which is placed on top and has a lid, is perforated on the bottom so that it holds the couscous in place while allowing steam to enter. Once the couscous is steam-cooked the lower pot may be used to simmer and serve the prepared dish.[1][2]