145 minutes before serving, light the grill. Half and hour before serving cover the fish steaks with the sesame oil, tamari, lime juice, mirin, garlic, ginger and pepper flakes. Let them sit 10 minutes in the marinade. Remove from the marinade and lightly dip in vegetable oil. Set the steaks on the grill and grill 5 to 7 minutes per side. When done brush with marinade and garnish with lime.