London broil is such an easy, fast dinner really. Most often, you will find that it is a marinated flank or top round that is cooked over very high heat and served rare. For this London broil I used a 1.5 lb top round and generously applied my special coffee rub which is basically coffee, garlic powder, onion powder, cayenne, black pepper and kosher salt. Wrapped it up and placed in the fridge for about 48 hours. I then pulled it out to come up to room temp while I got the grill going. You can see how dark it is from sitting with the coffee rub for so long.