Classic London Broil

Why This Classic London Broil Works

During the long rest in the marinade, the soy sauce, vinegar, lemon juice, and Worcestershire start to work their way into the surface of the flank steak. The salty soy and the acid from the vinegar and lemon loosen up the tough outer fibers, so the steak doesn’t tighten into a chewy slab under high heat. Olive oil coats the meat, so it doesn’t dry out as fast under the broiler.

As the steak broils, the outside browns quickly while the inside stays juicy. Because the meat is already seasoned all the way across the surface, it doesn’t need much time under the heat to taste good. Shorter cooking time means the juices stay inside instead of running out.

After it comes out of the oven, those few minutes of resting let the hot juices settle back through the steak instead of spilling out on the cutting board. Then slicing thinly against the grain cuts through the long muscle fibers, so each bite feels tender even though flank steak starts out as a tougher cut.

Mistakes To Avoid

Letting the steak sit in the marinade for only an hour or two leaves the center tasting plain while the outside picks up all the seasoning. The meat ends up with a strong outer layer and a middle that feels like unseasoned roast beef instead of a well-soaked steak.

Putting the steak too close to the broiler flame can scorch the outside before the inside warms up. The surface turns dark and hard while the middle stays chewy and underdone, so it becomes tough to slice thinly and chew.

Cooking the flank steak past medium under the broiler dries it out fast. The lean meat tightens, pushes out its juices, and comes out firm and stringy instead of juicy with a bit of chew.

Skipping the resting time after broiling sends the juices running all over the cutting board as soon as the knife goes in. The slices look dry and dull, and the steak feels less moist even though it was cooked correctly.

Slicing the steak with the grain instead of against it leaves long muscle fibers in each piece. Each bite feels ropey and hard to chew, even if the steak is perfectly cooked and well-marinated.