Heat the oven to 375°F. Grease a 9×13-inch baking dish.
Cook the penne in well-salted boiling water for 2 minutes LESS than the package directions (it finishes cooking in the oven — this is what keeps it from going mushy).
In a large bowl, whisk the cream of chicken soup, sour cream, cream cheese, chicken broth, garlic powder, onion powder, salt, and pepper until mostly smooth (a few cream cheese lumps are fine — they melt in the oven).
Fold in the shredded chicken, 1 cup of the mozzarella, and the drained pasta. Toss until everything is coated.
Spread in the baking dish and top with the remaining 1 cup mozzarella and the Parmesan.
Bake uncovered 28 to 32 minutes, until the top is golden and the edges are bubbling. Rest 10 minutes before serving so it sets up. Shower with parsley.