make the sauce by simmering the soy sauce, honey, mirin, and sake together. off heat, stir in sesame seeds.
freeze the steak briefly to make for easier slicing.
slice steak into scant 1/2-inch-thick pieces
pound steak slices into think strips.
layer a few strips of steak together then lay scallions over top.
using a knife, scoop up the edge of the steak and start to roll...
roll steak tightly around scallions.
secure rolls with toothpicks.
grill rolls until charred and cooked through, brushing with sauce occasionally.
serve as an appetizer or plate them up with some charred snap peas and rice for a full meal!