Beef Porterhouse SteakSometimes referred to as the King of the T Bones, the Porterhouse Steak is indeed a sort of plus sized T Bone Steak; both are cut from the same part of the animal (the sirloin), and include prime fillet and tenderloin on their distinctively shaped bone. The main difference is that the Porterhouse Steak includes more tenderloin, because it is cut from the rear end of the sirloin, and it is sized so generously that it will feed two adults comfortably.