To make the chimichurri sauce, place all of the sauce ingredients into a food processor. Pulse until smooth. Remove from the food processor and place in a bowl. Refrigerate until ready to use. If ingredients separate during refrigeration, mix together before serving.
Liberally sprinkle the skirt steak with salt and pepper on both sides.
Pre-heat a heavy-bottomed pan to medium-high heat. Add a drizzle of vegetable oil to coat the bottom of the pan. Cook the steak for 3-4 minutes on one side. Flip and cook for an additional 4 minutes for medium-rare.
Remove the steak from the pan and let rest for 5 minutes. Slice thinly against the grain. Drizzle half of the sauce over the steak. Reserve the other half for individuals to add as they like.