marinade for flank steakreserve at least 1 cup for basting
Marinate flank steak in a covered dish or gallon bag in the refrigerator for several hours (24 hours is ideal, but no more than 72). If you're unable to marinate the steak, sprinkle liberally with coarse salt and sprinkle lightly with pepper on all sides several minutes before grilling.
Place steak on a high heat grill and sear on each side for 2 - 3 minutes. Baste frequently.
Turn heat down to medium and continue cooking (flipping and basting) until you reach your desired internal temperature as read by a meat thermometer.
Allow steak to rest about ten minutes before slicing thinly against the grain.