Flatiron steak. It's not how they cook it but how they cut it. The flatiron is actually a cool name for the blade of the chuck or shoulder of beef. Although some parts of the shoulder are tough and need to marinate, others like the flatiron are especially tender. But it took university researchers in Florida and Nebraska to figure out how to trim the old chuck roast into new cuts like flatirons, ranch steaks and petite roasts. All are fine on the grill.
_ CHRIS SHERMAN, Times food critic