Preheat your oven to 400℉.
Prick the sweet potatoes with a fork to let the steam escape. Place onto a parchment-lined baking sheet and bake for about 1 hour (depending on the size). You'll know they're don when a knife/fork slides in easily.
While they bake, brown the butter on the stovetop.
When they're soft inside, remove from the oven and cut a slit on the top. Carefully, spoon out the insides into a medium bowl. Try to not rip the skin too much.
In the bowl with the sweet potato, add the cinnamon, salt, maple syrup, milk, and browned butter. Mix/mash (to your liking) to combine.
Spoon the sweet potato mixture back into the skins.
Top with a sprinkle of brown sugar and pecans or marshmallows, and bake for another 10 minutes.
Enjoy warm!