This cut might just be God's gift to poor dudes that love good beef. According to researchers at the University of Florida and the University of Nebraska, this cut of beef is the second most tender cut after the tenderloin. However, unlike the tenderloin, it is full of rich, beefy flavor, closer to that of the ribeye. And - the best part - it's cheap. I think I find it regularly at Kroger for maybe $6/lb or less, I can't recall exactly, but check it out!
When you pick out a flat iron, pay close attention to the consistency of its thickness. You want to get one that has the most consistent thickness. All of them will go from thick to thin, but for some it is less dramatic and thus you will get more even doneness.
I've cooked these several ways but settled on one method that I use most frequently.
First, let the steak get up to room temperature - this is an important step in any steak you cook. Then, season with a bold rub - I like to do these with a mixture of Dizzy Cow Lick and Jamaican Firewalk, or for an even richer flavor I'll throw in some freshly ground coffee. Bold rubs go well with the beefy flavor of this cut.
Get your Egg up to lava temps (700+) and sear for 60 seconds per side. Now, because this is a thin cut, I do not pull the steak off at this time for a 20 minute rest. Instead, I close the dome and get the Egg to around 600 degrees, and I go about 3.5 - 4 more minutes on each side, or until the internal temp reads about 125.
Pull the steak off the Egg, wrap in foil, and let it sit for 10 minutes. You're gonna want to slice it right away but LET IT SIT! This will keep the juices in the meat once you do slice.
Finally, slice thinly ACROSS the grain and enjoy. Using an electric cutting knife helps here.
Enjoy!