Preheat oven to 350°F; grease a 9x13-inch dish.
Hand-crumble raw beef into small pieces in dish; combine with uncooked noodles, mushrooms, onion, and garlic.
Whisk broth, soup, sour cream, Worcestershire, paprika, salt, and pepper separately until smooth.
Pour sauce over beef and noodles; stir to combine evenly.
Cover tightly with foil; bake 35 to 45 minutes, stirring after 20 minutes, until noodles are tender and beef reaches 160°F (71°C) throughout.
Uncover; top with mozzarella and bake 5 minutes until melted and golden.
Stand 5 minutes; garnish with parsley and serve hot.