For the marinade, place honey, shaoxing and soy sauce in a non-reactive bowl and stir until dissolved. Add remaining marinade ingredients and thoroughly combine.
Place steak in marinade and coat well. Leave to marinate for at least 4 hours, preferably overnight in the fridge.
Remove steak from fridge and allow it to come to room temperature. Preheat barbecue on high and make sure the grill is clean and well-oiled.
Take steak out of marinade. Blot dry with paper towels to remove any excess marinade. Rub a little oil on the meat. Cook over a high heat for about 3 minutes on each side.
Remove steak from grill and cover loosely with foil. Allow it to rest somewhere warm, still covered, for 10-15 minutes before carving. Slice across the grain.
Serve on a platter, pouring any resting juices over the steak. Garnish with spring onions and sesame seeds.