Combine ½ cup extra virgin olive oil, red wine vinegar, parsley, cilantro, garlic, red pepper flakes, lemon, and ground cumin in a high-speed blender or food processor. Season with salt and black pepper, to taste, and blend until smooth. Taste and adjust seasonings as desired. Set aside.
Heat a cast iron grill over medium heat and brush the surface with half the remaining olive oil. Once the grill is hot, add the steaks. Brush with the remaining olive oil, and season with salt and black pepper, to taste.
Cook steaks over medium heat for approximately 4-5 minutes before turning. Continue cooking for another 4-8 minutes, depending on how well you’d like the steaks done. Check the internal temperature with an instant-read thermometer after 4 minutes to determine final cooking time.
Remove from heat and allow the steaks to rest for 5 minutes before slicing and serving with a drizzle of the green sauce and your choice of sides. Enjoy!