Fajitas are all about the sizzle. That's what we love about them. And as far as proteins go, nothing sizzles like steak. A true old-school fajita can be nothing more than seasoned slices of sizzling skirt steak wrapped up in a toasty fresh flour tortilla. It's the definition of simple perfection. Add some colorful veggies, herbs and a bit of sauce, and you've got one heck of a lean, mean hunger satiation machine. These fajitas are all about the beef. Skirt steak is preferred for it's robust flavor, but you can use sirloin flap, flank steak, or anything else you like. A fatty cut like rib eye might be too unctuous for most, but to each his own. Skirt steak should be tenderized, usually with a marinade, then seared hard in a cast iron pan for maximum sizzle. Cook the steak to an internal temperature of 125-130 f, then let it rest while you cook the veggies. With simple prep, huge flavor, and straightforward cookery, these fajitas make a great special with a strong shot at a spot on the regular menu. Once you master the recipe, mix it up. Try a new marinade or different veggies. Just don't forget the sizzle.