London Broil is a beef-based food dish usually made by broiling or grilling marinated flank or round steak and then cutting it against the grain into thin strips. For other uses, see Beef (disambiguation). ... Wikibooks Cookbook has more about this subject: Broiling Broiling is a process of cooking food with high heat with the heat applied directly to the food, most commonly from above. ... Grilling means cooking directly under a source of direct, dry heat. ... Marination, also known as marinading, is the process of soaking foods in a seasoned, often acidic, liquid before cooking. ... The flank steak is a beef steak cut from the stomach muscles of the cow. ... To meet Wikipedias quality standards, this article or section may require cleanup. ...

Although many butchers will label a cut of meat "London Broil", the term does not refer to a specific cut. The cut of meat traditionally used is flank steak, but top round roast/steak is also commonly used. Because the muscle fibers run the entire length of these cuts, the meat can be tough if not tenderized via pounding or massaging. Scoring, stabbing, cutting, penetrating, or otherwise mutilating the cut before sending it into the broiler will ruin an expensive piece of beef by letting all the desirable bloody juices run out of the meat into the pan. Before broiling the whole pieces, the beef should "set" for five minutes outside of the oven to give the juices time to congeal a little bit; otherwise, the blood will just end up in the plate. In cooking, tenderizing is a process to break down collagens in meat to make it more palatable for consumption. ...

The preparation of London Broil typically involves marinating the meat for several hours followed by heating in an oven broiler or outdoor grill. In both heating methods the meat is placed approximately three inches from a direct heat source and turned several times to promote even cooking and avoid burning. It is commonly served in thin slices, cut across the grain.

Despite its name, this is entirely an American invention.^{[citation needed]}

London boil is cut against or across the grain, vis a vis the grain.

Against or across the grain it is cut.