This is going to generate some smoke, so again, make sure to keep it a good six inches from the flame or broiler element, and if you're doing this indoors, turn on your kitchen ventilation fan!
London Broil is not generally the most tender cut of beef, hence the lower price. The keys to keeping it from turning into shoe-leather, are to allow it to rest well, once cooked, and slicing it thinly across the grain.
Want to have this during the week, but don't have time to grill on your average weeknight? Go ahead and grill this up when you're grilling other things on the weekend and cut the cooking time by 2 minutes per side. Remove from the heat, allow to cool, and wrap in foil and refrigerate whole. Slice thinly while cold and lay the slices out on a baking pan. Brush the exposed surfaces with a little cold coffee and cover with another sheet of foil. Heat in a 350º F oven for about 15 minutes, or heated through.
—Renée (RJ Flamingo) Joslyn
ground coffee (not instant!)
ground chipotle chili powder
2-3 lbs. London Broil, at least 1-1/2" - 2" thick