01 - Set the oven temperature to 400°F.
02 - Pierce each sweet potato multiple times with a fork and place them on a foil- or parchment-lined baking sheet.
03 - Bake for 50 to 60 minutes until tender when pierced with a knife.
04 - Remove from oven and let cool slightly. Slice each potato lengthwise without cutting all the way through.
05 - Fluff the interiors with a fork, drizzle with melted butter, then sprinkle with brown sugar, cinnamon, nutmeg, and salt.
06 - Top each potato with an even layer of mini marshmallows.
07 - Return baking sheet to oven and bake 5 to 7 minutes until marshmallows are golden and toasted, watching closely to prevent burning.
08 - Serve while hot.