Place the sweet potatoes on a baking sheet and bake at 375°F for 45 minutes to 1 hour, or until they easily give with a slight pinch (wearing an oven mitt). Remove from oven and let cool enough to handle. Lower the oven temperature to 350°F.
Once cooled, remove skin and transfer to a medium-sized sauce pot over medium heat.
Add the butter, sugar, spices, and coconut milk to the pot with the sweet potatoes. Bring to a simmer, stirring continuously.
Using an immersion blender, standing blender, or food processor, blend the mixture until completely smooth. Set the filling aside to cool.
In a separate bowl, whisk the eggs with the vanilla extract and set aside. Once the sweet potato filling is slightly cooled, whisk in the egg mixture until smooth, and pour the filling into the pie pan.
Bake at 350°F for one hour, or until the center stops jiggling. Let the pie cool on the counter and then transfer to the refrigerator to cool completely.
Serve with whipped cream and a fresh grating of nutmeg, and enjoy!