Preheat the oven to 375 F. Lightly spray a 9×13-inch baking dish with cooking spray and set it aside.
In a small bowl, combine the Italian seasoning, garlic powder, ½ teaspoon of salt, and ¼ teaspoon of pepper.
Sprinkle the mixture over both sides of the chicken breasts and place them in the bottom of the prepared baking dish.
In a medium bowl, mix the chopped tomatoes, basil, lemon juice, olive oil, balsamic vinegar, and the remaining ½ teaspoon of salt and ¼ teaspoon of black pepper.
Spoon the tomato mixture over the top of the chicken in the pan.
Bake in the preheated oven for 25 minutes.
Remove the pan from the oven and place the sliced mozzarella evenly over the chicken.
Return the pan to the oven and bake for an additional 10 to 15 minutes, until the cheese is melted and the chicken is cooked through.
Remove the pan from the oven, drizzle balsamic glaze over the chicken, and top with chopped basil if desired.