Preheat your oven to 350°F (175°C).
In a large pot, bring salted water to a boil and cook the penne pasta according to package instructions until al dente. Drain and set aside.
In a large mixing bowl, combine the cooked chicken, minced garlic, heavy cream, chicken broth, ¾ cup of grated Parmesan cheese, Italian seasoning, salt, and black pepper. Mix well.
Stir the cooked pasta into the chicken mixture until everything is evenly coated.
Transfer the pasta mixture into a greased 9x13-inch baking dish.
Top the pasta with the remaining Parmesan cheese and mozzarella cheese, spreading it evenly.
Drizzle olive oil over the top of the cheese.
Bake in the preheated oven for 25-30 minutes, or until the cheese is bubbly and golden brown.
Remove from the oven and let it cool for a few minutes before serving.
Garnish with chopped parsley before serving.