Place flank steak in a gallon-sized resealable bag. In a small bowl, whisk together marinade ingredients and pour over steak. Seal bag and refrigerate for at least an hour, preferably overnight.
Combine all chimichurri ingredients in a blender or food processor until smooth; set aside.
Heat a nonstick skillet or grill to medium-high heat. Cook steak for 6-8 minutes on each side until browned on the outside and slightly pink in the center.
Thinly slice steak across the grain and serve with chimichurri sauce on top.
Notes
MFP: MFF Flank Steak with Chimichurri SauceOctober 2022