I'm making a sweet potatoe casserole for Thanksgiving with butter, cinnamon, nutmeg, a little salt 'n pepper and, of course, slices of sweet potatoes. Can I safely freeze this until two days before Thanksgiving and then bake it? Or should I bake it first and then freeze it? The potatoes are already cooked. We're having 15 people with a 27 pound turkey so not lots of extra time. Everyone brings their specialty and they want my sweet potatoes, every year!! What do you think? Thanks and a very Happy Thanksgiving.