Servings: Serves 4
Preheat a grill or grill pan on medium-high heat. Using a sharp knife, chop the chipotle chili as fine as possible, trying to break up any large pieces.
In a medium mixing bowl, combine the chipotle with the paprika, oregano and sugar and mix thoroughly. Lay the steaks out on a plate and season with salt and black pepper on both sides. Season generously with the spice rub as well on both sides. Brush the grates of the grill with a bit of oil, and grill steaks for 4 to 5 minutes on each side or until medium rare (135° internal temperature with a thermometer).
While the steaks are grilling, combine the garlic and herbs in a mortar and pestle or food processor and grind into a paste. Add the crushed red chili, lemon zest and vinegar and mix well. Slowly drizzle in the oil while mixing and season to taste with salt and pepper. Reserve for serving.
Remove steaks from the grill to a plate or rack and allow to rest for 3 to 4 minutes. Serve steaks with the chimichurri sauce.