London broil, despite what you might find at the local meat market, is not a cut of beef. Rather it is a method of cooking a piece of beef that is potentially tough and chewy. Grill the marinated flank steak hot and fast and to no more than medium. Overcooking will make the meat tough no matter how long it was marinated. For a thick roast, grill it directly for about 2 to 4 minutes per side, and then indirectly for up to 30 minutes. The internal temperature should not pass 135 F. The steak can also be slow-cooked for rich-tasting, tender results.
Always cut against the grain of the meat for maximum tenderness.
This flavorful cut ranges from 1.75-2.5 pounds.