Flank Steak Grill Question

Frank steak is the center of my favorite meat meal off my small egg. In fact it is what I painstakingly make for my own birthday meal! Flank steak will become tough if overcooked. In order to assure it starts out tender I Jaccard mine plus I marinate it for 30 to 48 hours in a concoction of EVOO and garlic. As for egging it I go direct at a fire of 650 to 700º merely for 2 minutes per side and I'm done. Of course you probably already know this but be sure to cut the meat crosswise with the grain.