Preheat your grill to high or preheat a ridged grill pan until very hot.
Rub the steaks with the olive oil and season them with salt. Grill the steaks for 3 to 4 minutes on each side for a medium-rare to medium, or longer for medium-well or well done. Serve with Chimichurri Sauce
To make the Chimichurri, place the vinegar, lemon juice, parsley, oregano, and garlic in a blender and puree. With the motor running, add the olive oil, blending until the sauce comes together. Add the red pepper flakes and salt and pepper, to taste.
Place in an airtight container and refrigerate for up to 1 day. Serve at room temperature.