Calkins and Johnson focused on the cheaper parts of beef, the chuck and the round, to see if a desirable steak could be produced from either of these.

The research teams at both schools found that the top blade of the chuck, specifically the infraspinatus muscle, contained tender meat, but there was a large seam of tough connective tissue down the middle that had to be removed.

This cut is anatomically distinct from the shoulder tender, which lies directly below it and is the teres major.

This method of breaking down the larger cut was creation of the flat iron steak as we know it today.

As a whole cut of meat, the top blade usually weighs around two to three pounds; it usually yields four steaks between eight and 12 ounces each.