Tournedos is a term of French origin attributed to a slice of beef tenderloin, obtained from the "heart" of the tenderloin itself. It must have a thickness of 1 inch and a weight of about 4-5 oz.
It is generally cooked in a pan or grilled (cooking must be short) and served napped with its sauce or with maître d'hôtel butter (scented with parsley and lemon juice).