Place steaks in glass dish or plastic zip lock bag and pour marinade over. Marinate at least 6 hours or overnight. Drain. Grill over medium hot coals for 2-3 min, then flip and cook second side 1-2 min. The amount of time depends on thickness of steaks and intensity of heat but Wills (Steven Wills of the Western Canadian Bison Ranch with a herd of 50 animals) says you must take great care not to overcook the meat. Grill at a slightly lower temperature than beef and don't pierce with a fork! Remove from grill and let steak stand 5 minutes before serving. Serve with grilled vegetables.