Preheat the oven to broil, 430°F (220°C).
Season chicken breasts with salt and pepper.
Heat the oil in a frying pan on medium heat.
Once the oil is hot, add the chicken and cook for about 3-5 minutes on each side until cooked through. You can use a meat thermometer to make sure it's 165°F (73°C). Remove the chicken and let it rest.
In an oven-proof dish, add half the marinara sauce and place the chicken breasts on top of it. Pour in any remaining juices from the chicken.
Top the chicken with the remaining marinara sauce, mozzarella, and finally the parmesan. Broil in the oven for about 5 minutes or until the cheese is golden.
Serve the chicken parmesan with leafy greens and tomatoes.
