Seriously who would think that you would get Irish mashed potatoes from an italian girl but it is true - actually I got this from my psuedo mother in law (the man hasn't married me but she is my mom) and she taught me how to make it with love! Enjoy!
Cook potatoes in boiling water - then drain and mash.
Beat in remaining ingredients until mixed with potatoes (a fun variation is to through in some chedder cheese but take out the salt or it gets to salty!)
Put in a lightly buttered caserole dish - cover and refrigerate it over night (you can skip this if you want but there is something about letting the falvors combine. I have done it both ways for my family. They don't notice but I do!)
Take out let stand for five minutes while preheating the oven to 350 degrees. Bake for 30 minutes. (Another nice touch is sprinkling paprika on top before baking.)