A hanger steak, also known as the butcher’s steak or the hanging tenderloin, is a cut of beef steak prized for its flavor. This cut is taken from the plate (the upper belly of the animal) where it supports the diaphragm. In the past, it was known as the “butcher’s steak”, because butchers would often keep it for themselves rather than offer it for sale. This is because the general populace believed this to be a crude cut of meat, although it is actually one of the most tender.
The hanger steak resembles the flank steak in texture and flavor. It is a vaguely V-shaped pair of muscles with a long, inedible membrane running down the middle.
The only problem is… there’s only ONE per animal. 
Since this cut comes from a supportive muscle, rather than an active muscle, it is more tender, but can be tough when improperly prepared. The tenderness suffers when exposed to long periods of dry heat, but… who would dare insult such a ‘rare’ cut of beef by cooking it above medium rare anyway??? 
