Preparation Season chicken cutlets on both sides with salt and pepper and set aside. Whisk together mayonnaise and 1/4 cup chimichurri in a large bowl. Reserve remaining chimichurri. Add chicken cutlets to the mixture and turn to coat. Cook immediately, or for better flavor, transfer to a sealed container and refrigerate for 4 to 24 hours. Heat a gas or charcoal grill over high heat for 10 minutes. Cook chicken cutlets directly over high heat, turning and flipping occasionally, until just cooked through and lightly charred all over, about 4 to 5 minutes. Transfer chicken to a serving platter. Spoon some of the remaining chimichurri over the chicken and serve the rest in a small bowl on the side.