Red dog filet is a type of steak made from the tenderloin section of a beef animal. It is also known as "hangar steak" or "châteaubriand," and it is prized for its tenderness and flavor. The name "red dog" supposedly comes from the fact that the meat is often cut from red cattle, and the term "filet" refers to the fact that it is a thin, boneless steak. Red dog filet is typically grilled or broiled and served with a sauce or other accompaniments.