To begin, combine the olive oil, parsley, cilantro, vinegar, onion, garlic, oregano, red pepper flakes, and juice from the lemon in a food processor or a blender.
Process until the ingredients create a smooth sauce.
Set it aside for now.
Heat your grill to medium high heat.
Salt and pepper the steaks.
Cook the steaks on the grill for about 4 minutes on each side, or until cooked to your desired level of doneness.
Allow the steak to rest for 5 minutes before cutting it into slices.
Serve with the chimichurri sauce.
Swoon.
Enjoy!
Notes
Some people have a genetic marker that causes cilantro to taste like metal or dish soap. They can't help it, it is science. If you are one of them, simply substitute the cilantro for all parsley.