Slice each chicken breast in half horizontally to make the chicken thin. This will help make your chicken extra tender and help it cook more quickly.
Season the chicken with salt and pepper and place it into a large gallon-size plastic bag.
To a small bowl add the olive oil, balsamic vinegar, garlic powder, and Italian seasoning and whisk well. Pour half of this mixture into the bag with the chicken and place in the refrigerator to marinate for at least one hour.
Preheat the oven to 425℉.
Place all of the vegetables into a large bowl with the remaining marinade and stir to coat the vegetables well.
Spray a rimmed baking sheet with nonstick spray and arrange the marinated chicken and vegetables evenly across the sheet pan. Bake for 25 to 30 minutes or until the chicken is completely cooked through. Sprinkle the parmesan cheese over everything. Enjoy!