The hanger steak is from a muscle used to support the diaphragm of the beef. It doesn't do a ton a work, so it is extremely tender and delicious.
This is a high and fast cook. Season the outside with salt and pepper and pre-heat some grape seed oil in a pan until it’s nice an hot. This cut takes under 10 minutes to cook and should be kept rare to medium rare. After resting, slice and sprinkle with some flake or finishing salt.