Place the steak in the freezer for half an hour to firm the fat.
Heat a griddle or large cast-iron skillet over high heat for 5 minutes.
Remove the steak to a cutting board and using a long, thin carving knife, cut the steak horizontally (think the streets of Manhattan rather than the avenues) into 1/4- to 1/3-inch strips. If wider pieces are desired, cut on bias. Try to use a minimum of back and forth "sawing" while slicing.
When the skillet is hot, quickly sear each slice 20 to 30 seconds per side and remove to a platter. Serve immediately with a sprinkling of sea salt or soy sauce.