To make ahead of time, cover unbaked mashed potato mixture tightly with foil and refrigerate no longer than 24 hours. Uncover and bake 40 to 50 minutes.
This recipe is great to double for those hearty appetites! Cook the potatoes in Dutch oven. Use 3-quart casserole and bake uncovered 35 to 40 minutes. If you make it ahead and refrigerate, bake 40 to 50 minutes.