Whisky all marinade ingredients together in a medium bowl - transfer mixture to a large, sealable bag and add steak. Squeeze out excess air to ensure that meat is evenly marinated. Marinate 6-8 hours in the refrigerator.

Remove the steaks from the marinade and pat off excess marinade with a paper towel. Preheat BBQ to medium-high heat and grill about 5 min. on each side until medium-well (155F). Let rest in a warm place for another 10 min to finish cooking. To serve, slice steak and sprinkle with green onions and sesame seeds.