This delightful one-skillet cheesy chicken Alfredo casserole combines penne pasta, tender broccoli and shredded rotisserie chicken smothered in a creamy sauce. To simplify the sauce, we opt for a pre-shredded Italian cheese blend. Though cheese blends vary, they typically contain Parmesan cheese, imparting the traditional Alfredo flavor. Seek blends with aged cheeses or blends that include sharp cheeses like provolone or Asiago for a richer flavor profile.