Matambre

Matambre is the name of a very thin cut of beef in Argentina, Uruguay, Rio Grande do Sul and also Paraguay. It is a rose colored muscle taken between the skin and the ribs of the steer, a sort of flank steak. It is not the cut known normally in the U.S. as flank steak. Some people refer to it as the "fly shaker", because it is the muscle used by the animal to twitch to repel flies and other flying insects. The same word is also used for a dish made of a matambre meat roll stuffed with vegetables, peppers, ham, hard-boiled eggs and herbs, then boiled or oven-roasted. It is served sliced—with the fillings making a colourful display—either hot or cold. It is often eaten with chimichurri sauce[citation needed]. It is a rather fatty meat and is usually eaten with vegetables. Pork matambre is also used. The name matambre is formed from the combination of "matar" and "hambre" ("hunger killer").

Source: Wikipedia