When you are ready to cook the meat, remove it from the marinade and brush off all bits of garlic and any excess sugar.
Garlic will burn during cooking and become bitter.
Pat the steak dry, and let it come to room temperature before cooking.
Flank steak should be cooked quickly over high heat, and outdoor grilling is a common approach.
The best way to cook flank steak indoors is on the stove in a grill pan or cast-iron frying pan.
Make sure that the pan is heated until just before smoking so that the meat sizzles when it hits the surface.
If you are grilling your flank steak, preheat the grill to 450 degrees. High heat will sear the beef and seal in the flavors.
Grilling or pan searing for 4-5 minutes per side should produce an internal temperature of around 135 degrees or medium-rare.
Flank steak tastes best rare to medium-rare.
Remove the steak from the heat, tent with foil, and let it rest for 10 minutes.
The marinade preserved from before combing with the meat can be drizzled over the steak while it rests.