Hanger steak is one of the fuller-flavored and beefier cuts of meat. It's used a lot in Mexican, South American and Southeast Asian dishes. I love to serve it with an explosively tasty and herbaceous chimichurri sauce.
To marinate the steak:
In a large zip-top bag, combine the olive oil, garlic and black pepper to taste. Add the steaks to the bag, seal and toss to coat. Place the refrigerator and let marinate at least one hour.
To cook the steak:
Heat a pan until hot but not smoking. Season the meat with salt and place in the pan. Cook, undisturbed, until browned, about 2 minutes, then turn and cook until browned on the other side, about 2 additional minutes. Continue to brown all the way around evenly until all sides are browned (using tongs to turn the meat to brown the edges, if necessary).
Add a spoonful of butter and baste the steak, spooning the melted butter over the meat continuously for 1 minute. Remove the meat from the pan and allow to rest for 6 minutes before slicing.
To make the chimichurri sauce:
Combine all ingredients but the vinegar in a food processor and mix well. Just before serving, stir in the vinegar. Put the chimichurri sauce in a bowl for drizzling over the steaks.