[#40, Hanger Steak, Bistro Steak, Butcher's Steak; Onglet (French)]
This is part of the diaphragm muscles and hangs down between the 12th and 13th ribs next to the kidneys, thus the name. There's just one per beef, weighing 1 to 2 pounds, and due to its internal position it doesn't show up on beef charts. It is flavorful, but like the skirt steak (another part of the diaphragm) it needs to be cooked briefly with high heat to no more than medium rare. Traditionally butchers kept this cut for themselves.
Some descriptions of this cut attribute it to the Plate cut, along with the Skirt Steak, but the NAMP manual associates it with the Short Loin, as it hangs quite high in the beast. The photo specimen was untrimmed, with fat and membranes in place. It measured 11-1/2 inches long, 5 inches wide and 1-1/2 inch average thickness, weighing 2 pounds 3-1/2 ounces.
More on Cuts of Beef.
Prep: This cut may have been trimmed by the butcher, with fat and membranes removed. If not, trim it yourself. There's a tough membrane between the two halves and the halves are usually separated before cooking.
Cooking: This is a loose grained piece of meat, similar to the Skirt Steak and requires the same sort of treatment to prevent it from becoming tough. Grill or Broil with high heat for a short time - no farther than medium rare. Slice it crosswise.