I got this recipe from my SIL, Melinda.I'm kind of a wuss so I only use 1 tablespoon of the red pepper flakes but you can make these as HOT as you like.
This is my personal rendition on a favorite from Quebec. The addition of pumpkin to ordinary mashed potatoes gives them an nice earthiness that goes well with roasted poultry or other autumnal fare. I have not tried it with canned pumpkin but will experiment eventually. Though I don't cook much with butter, you should feel free to add some more to suit your taste.