When I defrosted the london broil to make the stir fry, it turned out that there were two "steaks" in the the package. I didn't need that much meat for the stir fry, so I saved the other one. Since my rice cooker broke, an other stir fry wasn't the ideal solution, so I decided to do a basic London Broil instead.
In searching the web for interesting ways to make it, I found this recipe from Simply Recipes. I have had good success the Elise's recipes, so I decided to make it. Basically you rub ground mustard seed into the meat and then briefly sear it in a cast iron pan. My only change to the recipe was that I used olive oil instead of butter.
It turned out well. Not as tough as I expected it to be and quite tasty. Served it with some basic veggie sides -- green beans and corn if I remember right. A nice quick meal.