In a jar or a can, it is cooked at 110°C all the way thru. It can be kept for several years at room temperature, all the more so as its texture develops over time: the foie gras absorbs its own fat, thereby gaining in smoothness as it ages !
Whole duck Foie Gras in a glass jar
Block of Duck Foie Gras in tin
Block of Foie Gras Duo (Block of Duck Foie Gras and Block of Goose Foie Gras )