Stir the oil and herbs in a small bowl to blend. Season with salt and pepper. Brush both sides of the cutlets with the herb oil. Heat a heavy large oven-proof skillet over high heat. Add the cutlets and cook just until brown, about 2 minutes per side. Remove the skillet from the heat.
Spoon the marinara sauce over and around the cutlets. Sprinkle 1 teaspoon of mozzarella over each cutlet, then sprinkle 2 teaspoons of Parmesan over each. Sprinkle the butter pieces atop the cutlets. Bake until the cheese melts and the chicken is cooked through, about 5 minutes.