01 - Preheat your oven to 400°F. Lightly grease a baking dish with olive oil.
02 - Place chicken breasts in the prepared dish. Season both sides generously with salt and pepper.
03 - Spread 1 tablespoon of pesto evenly over the top of each chicken breast.
04 - Layer tomato slices over the pesto-coated chicken, distributing evenly among the breasts.
05 - Place mozzarella slices over the tomatoes. Sprinkle grated Parmesan on top if using.
06 - Lightly drizzle olive oil over the entire dish.
07 - Bake for 25 to 30 minutes until chicken reaches an internal temperature of 165°F and cheese is golden and bubbly.
08 - Remove from oven, garnish with fresh basil leaves, and serve immediately.