Wash sweet potatoes and then prick with a fork all over. Place them on a lined baking sheet at bake at 425F for 60-90 minutes or until sweet potatoes are fork tender. This can also be done the night before.
When ready, preheat the oven to 350F and grease a non-stick pan. Set aside.
In a large mixing bowl, add in sweet potatoes, skins removed with the remainder of ingredients: vegan brown sugar, vegan butter, coconut milk, cinnamon, nutmeg, and salt. Mash with a potato masher until ingredients are well incorporated.
Add this mixture to the prepared baking dish and spread evenly. Top with vegan marshmallows leaving 1/2 inch from the sides. Place in the center of the preheated oven and bake for 25-30 minutes or until warm all the way through.
Broil for 5 minutes to toast the tops of the marshmallows. Watch this carefully so it does not burn.
Serve warm and enjoy!