Carmelized onions, gruyere cheese, bourbon...I could eat a bowl of just those three things. But this French onion pinwheel puts to use a cut that often gets turned into grind or stew meat, which is a shame because it stands on its own as a great steak cut. And that cut is the bottom round.
The original recipe from Over the Fire Cooking calls for a flank steak, but if you've ever butchered a deer there isn't much of a flank on one. Instead of a flank, I cut a bottom round lengthwise, then pounded it flat. This gives a similar cut to a flank and multiplies the uses of a bottom round. Using this same technique you can use a top or bottom round for roulades, tacos, or any other recipe calling for flank steak.
Why not use a backstrap? Backstraps, the holy grail of cuts for hunters across the country, are great but are too tender to be pounded thin. This turns them into mush. The hindquarter cuts provide enough structure to stand up to a meat mallet. Being a harder-working muscle they also have more flavor.