It’s possible to make relatively tough cuts like flank steak more tender by thinly slicing them against the grain—that is, perpendicular to the orientation of the muscle fibers—rather than with the grain. But how much more tender? America’s Test Kitchen decided to quantify just how much difference using the correct slicing method can make.

Flank steak contains wide muscle fibers and a relatively high proportion of connective tissue that make it chewy. Slicing it against the grain shortens those muscle fibers, making it easier to chew.

America’s Test Kitchen is a real 2,500 square foot test kitchen located just outside of Boston that is home to more than three dozen full-time cooks and product testers.