They sure can! Let them cool completely after baking. Cut into individual portions or leave uncut in casserole dish. Either way, wrap tightly with foil and freeze up to 3 months. When ready to enjoy, thaw in the refrigerator overnight or bake from frozen. Bake covered with foil at 375 degrees F until potatoes are hot and golden, 45 to 60 minutes. Double the time if potatoes are frozen.