01 - Preheat oven to 375°F. Grease a 9x13-inch baking dish with cooking spray or butter.
02 - Boil pasta in a large pot of salted water until al dente, about 2 minutes less than package directions. Drain thoroughly.
03 - Combine heavy cream, pesto, chicken broth, garlic, salt, and pepper in a large skillet over medium heat. Simmer for 2-3 minutes, stirring occasionally.
04 - Stir in Parmesan cheese until completely melted and sauce is smooth and creamy.
05 - Add cooked pasta, chicken, cherry tomatoes, and spinach to the skillet. Toss everything together until evenly coated with sauce.
06 - Transfer mixture to the prepared baking dish. Sprinkle mozzarella and additional Parmesan cheese evenly over the top.
07 - Bake for 20-25 minutes until cheese is golden brown and bubbly around the edges.
08 - Let the dish rest for 5 minutes before serving to allow the sauce to set. Garnish with fresh basil if desired.