A flat iron steak comes from the shoulder area of a cow, specifically the top blade of the cow muscle’s fine grain. This muscle is known for its tenderness, which makes a flat iron steak one of the most tender cuts of meat.
The grain is the direction in which the muscle fibers run in the steak. For flat iron steaks, you will typically see the grain running in one direction across the meat’s surface.
After your flat iron is cooked, it is important to identify the direction of this grain before slicing your steak. A flat iron should be cut into slices that are perpendicular to the direction of the grain. Cutting against or perpendicular to the grain allows the muscle fibers to shorten, making the steak more tender and easier to chew. Sometimes the grain can change directions while cooking, so it is important to adjust your slicing direction accordingly.
