2) Lightly brush the steaks with olive oil on both sides and season with salt and pepper. When the frying pan is very hot, add the steaks and sear over high heat for 3 to 4 minutes on each side.
3) Remove the pan from the heat and place it in the oven to finish cooking. For rare to medium-rare, keep the steak in the oven for 6 to 8 minutes (or until an instant-read thermometer inserted in the middle of the steaks registers 75C). When the steaks are cooked as desired, remove from the oven and allow to rest for another 4 to 6 minutes before slicing.
4) Combine all the ingredients for the chimichurri sauce in a food processor or blender and pulse until everything is chopped fine and well combined. The mixture should have the consistency of coarse pesto.
5) To serve, slice the steaks thinly against the grain and arrange on a platter. Drizzle some of the chimichurri sauce over the steak and sprinkle with toasted sesame seeds. Garnish with pineapple rings, if desired. Transfer the remaining sauce to a bowl and serve with the steak.
A viewer, who may not be a professional cook, provided this recipe. The Food Network Kitchens chefs have not tested this recipe and therefore we cannot make representation as to the results.