The tenderness of a piece of meat is directly related to the kind of work done by its muscle components. The tenderest beef steaks come from the loin muscles: the Longissimus dorsi, or top loin, and Psoas major, or short loin. Both are located on the back of the animal between the major ribs and the rump and comprise a muscle area much more lightly used than the legs or neck areas. While steaks in the adjacent rib area gain some of their tenderness from abundant fat-marbling in the meat, loin cuts generally gain their tenderness more from their location than their marbling.

Known by a wealth of names, tenderloin steak comes from the short loin and is probably the most tender of all beef steaks. Choose filet, tender steak or filet mignon to enjoy this nearly fork-tender meat. Filet flavor is less assertive than that of strip or sirloin steak. To maximize flavor, filet should not be marinated, heavily seasoned or cooked beyond medium, an internal temperature of 145 degrees Fahrenheit, the safe-temperature standard established by the United States Department of Agriculture.

Asking for a New York-cut steak in New York or a Kansas City-cut in Kansas City may yield only a puzzled look, but both names for strip steak are used outside those regions of the country. Depending on the region, strip steak may also be listed on a menu or in a meat case as hotel steak, ambassador cut, club steak, contrefilet or top loin. Steaks, including both top loin, tenderloin and the bone that lies between them, are porterhouse and T-bone cuts. A strip steak is basically a porterhouse or T-bone with no tenderloin portion. Flavor is full and hearty and needs only simple seasonings.

Sirloin steak nomenclature can be confusing. Boneless top sirloin steak actually comes from the top loin. Flavor is robust, but tenderness is unpredictable. Steaks cut from the sirloin itself are ordinarily bone-in and are described by the kind of bone they contain: pin-bone, flat-bone, round-bone and wedge-bone. Pin-bone, closest to the porterhouse and ribs, is the most tender. Wedge-bone, closest to the rump, is the least tender. Overcooking can diminish flavor. For a full-flavored sirloin, plan to broil or grill to medium, an internal temperature of 145 F.