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Tripe is the name given to the stomachs of various animals, but most recipes that call for it intend for you to use beef tripe. Cows have four stomachs, and the first three yield merchantable tripe. Blanket tripe = plain tripe = flat tripe = smooth tripe comes from the first stomach, honeycomb tripe (pictured at left) and pocket tripe from the second, and book tripe = bible tripe = leaf tripe from the third. Honeycomb tripe is meatier and more tender than the other kinds and considered to be the best, but all these kinds of tripe can be used interchangeably in recipes. Tripe is almost always sold bleached and partially cooked. This saves a lot of work, since unprocessed tripe would need to be cooked for many, many hours to make it tender enough to chew.