What is a Jersey Bean Crock? A Jersey Bean Crock or ‘les pais au fou’ is perhaps Jersey’s national dish. It is a tradition casserole of dried beans rather like a French Cassoulet. And don’t worry Guernsey readers I know that the Guernsey Bean Jar ( moussaettes au four ) is just as culturally important. The Bean Crock or Jar is cooked in a large clay casserole dish and historically was left in a baker’s oven overnight.