That’s a very good question, go ahead and fix the potatoes ahead of time, peel and cut into even sized chunks, place in cold water and simmer for about 15 minutes till you can smash a chunk with a fork. I usually add some white wine vinegar or concentrated lemon juice to the water once the potatoes are done (a tablespoon is enough and won’t hurt the flavor) and then drain, mash, and cool to room temperature. Note: If the potatoes are still a little wet, place back on the stove on low to take out some of the excess moisture before cooling. Once cooled and mashed, place covered in a plastic freezer bag with as much of the air removed as possible. Once cooked the enemy of potatoes is air, oxidation will turn the potatoes gray. You could also do this the day before and place the bag in the refrigerator. Once you thaw the potatoes on Thanksgiving, then add your butter, dairy etc. I do not recommend doing so before you freeze them, your dairy can curdle when you reheat them, amongst other things.

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