There is nothing more disappointing to a foodie than to screw up a nice flank steak by either over or under cooking it. Part of the problem is that the flank steak varies in thickness so the thin part will end up being well done while the thick part is still raw. My solution was to use the Anova Sous-Vide Cooker to cook the steak to 120 degrees for about an hour and then finish it off in a pre-heated cast iron skillet at medium high temperature. That way you get a consistent pink meat to go with that great sear. We like to serve the steak with oven roasted red potatoes that have been brushed garlic olive oil and green beans.