Preheat oven to 350°F.

Pierce each sweet potato several times with a knife and place them on a aluminum foil lined rimmed baking sheet.

Bake until sweet potatoes are very tender when pierced with a fork (about 1 hour).

Remove from the oven and let cool until able to handle.

Remove skins from sweet potatoes if desired and add them to a large bowl along with remaining ingredients.

Using an immersion blender or potato masher, blend all ingredients together until sweet potatoes are completed mashed.