This overnight scalloped chicken casserole is a comforting and delicious dish that can be prepared ahead of time. The chicken is cooked until tender and juicy, then layered with creamy sauce, cheese, and sliced potatoes. The casserole is then refrigerated overnight to allow the flavors to meld together. When ready to serve, simply bake until golden and bubbly. This casserole is perfect for busy weeknights or when entertaining guests, as it can be made in advance and requires minimal effort on the day of serving.