I like to keep the flank steak in it's natural form and beefy flavor, so I don't use the sauce as a marinated flank steak recipe, only as a flavor topping. I do like to use this chimichurri sauce as a marinade for chicken breast. It helps tenderize and keep an otherwise piece of lean meat from possibly drying out on the grill. Just give the chicken breasts a couple of pounds with a meat mallet tenderizer, then place the chicken and the chimichurri sauce in a gallon zip lock bag. Press the air out and then massage the bag a few times to distribute sauce. Marinate the chicken for two hours, then grill or bake on a foil lined sheet pan until internal temperature reads 165 degrees.