I make them a lot, because its lean. I poke holes all through both sides with a fork, then marinate (usually in the jewish teriyaki marinade--that stuff is really good) for at least 24 hours. Then grill on a preheated grill at medium high heat (I shoot for about 450* with the door closed) to get one side nice and seared, anywhere from 7-9 minutes depending how thick it is. Don't open the grill during this time, just chuck it on and dont open the grill for 7 minutes. It should be about 2/3 of the way cooked at this point. Then flip it, let it go for 5 minutes. Again, don't open the grill. If its not done after 5 minutes, turn the grill down a bit and bring it up to temperature--145*. This method will work unless its really thin or really thick.
Do NOT slice on the bias. That is only done by restaurants to make it look pretty. Slice it straight across in thin narrow strips. You want the fibers to be short, so it is tender. If you do this, I guarantee it will be tender and delicious. People make the "cut on the bias" mistake with flank steak and skirt steak as well. Tough meet needs to be cut across the grain, to keep the fibers as short as possible.
I challenge anyone on here who hates on london broil to make ti this way and tell me it isn't good. People always say "throw the london broil away and buy <insert fatty cut of meat>. Good steaks are great, no question. But a nicely made piece of london broil is good sometimes too. Its just a different thing. Its lean and economical.
Its honestly like saying, why would you eat pork chops? Throw them away and just eat 2 lbs of bacon for dinner.
