01 - Preheat your oven to 400°F. Lightly grease a baking dish with a small amount of olive oil.
02 - Arrange chicken breasts in the prepared baking dish. Season both sides generously with salt and freshly ground black pepper.
03 - Spread approximately 1 tablespoon of pesto evenly over the top of each chicken breast, covering the surface completely.
04 - Arrange tomato slices in a single layer over the pesto-covered chicken, distributing them evenly among the breasts.
05 - Place fresh mozzarella slices over the tomato layer on each chicken breast. Sprinkle grated Parmesan cheese on top if using.
06 - Drizzle the remaining olive oil evenly over the chicken and toppings.
07 - Bake for 25 to 30 minutes until chicken is cooked through (internal temperature reaches 165°F) and cheese is melted and golden brown.
08 - Remove from oven and let rest for 2 to 3 minutes. Garnish with fresh basil leaves before serving immediately.