Beef Tenderloin

The tenderloin is an oblong shape spanning two primal cuts: the short loin (called the sirloin in Commonwealth countries) and the sirloin (called the rump in Commonwealth countries).[3] The tenderloin sits beneath the ribs, next to the backbone. It has two ends: the butt and the "tail". The smaller, pointed end—the "tail"—starts a little past the ribs, growing in thickness until it ends in the "sirloin" primal cut, which is closer to the butt of the cow.[4] This muscle does very little work, so it is the tenderest part of the beef.