A cross rib roast is a square cut of meat that is a bit thicker at one end, has two or three rib bones and has alternating layers of lean meat and fat. The cross rib roast comes from the chuck primal cut, which is the area of the cow between the neck and the shoulder.
Since this area of the cow gets worked more, these cuts of meat are tougher. The considerable amount of connective tissue in cross rib roasts makes braising a good preparation choice. The moist heat of braising breaks down the connective tissue and makes the cross rib roast more tender.