Combine the parsley, basil, cilantro, olive oil, garlic, vinegar, lime juice, coriander, cumin, salt, and pepper in a blender for a couple of minutes to make the chimichurri sauce.
Preheat the grill pan and coat it with cooking spray. Combine the chili powder, salt, black pepper, and cayenne, and sprinkle the mixture evenly over both sides of the steak. Place the steak on the prepared rack and broil 3 to 4 minutes per side for medium rare. Transfer to a cutting board and allow the meat to rest 5 minutes. Cut across on the diagonal into 1/4-inch to 1/2-inch wide strips. Serve drizzled with the chimichurri sauce.