Happy New Year!
I have been looking for a way to make mashed potatoes the day prior to hosing for various holidays. I found this recipe at Once Upon a Chef and tried it. These are my new go-to mashed potatoes! The potatoes are really good, and fairly easy. In the past when I have tried to reheat mashed potatoes they have turned out gummy but these stay nice and creamy.
You can find the recipe here: https://www.onceuponachef.com/recipes/creamy-make-ahead-mashed-potatoes.html
You bake the potatoes instead of boiling them. Crazy right? I used a potato ricer to get the potatoes really smooth. I baked them the next day in a 350F oven, covered in foil, for 40 minutes (stirring once half way through). Delicious!