Put the chimichurri ingredients in a food processor and pulse until fully mixed. It should look like a green paste.
Fire up the grill, pat the steaks dry, season with ¼ teaspoon salt and ¼ teaspoon black pepper. The steaks are done when a thermometer registers an internal temperature of 145 °F
Let the steak rest for about 5 minutes before cutting into thin slices, against the grain of the meat.
Spoon the chimichurri sauce on top of the steak slices.