Preheat oven to 350 degrees F. Line a large baking sheet with parchment paper. Pierce potatoes with a fork. Bake sweet potatoes 45 minutes to 1 hour, or until softened. Remove from oven and cool slightly.
Slice sweet potatoes in half lengthwise. Scoop out most of potato flesh, leaving 1/4" border attached to potato skin. Mash potato flesh in a medium bowl with melted butter, salt and about 1 tbsp maple syrup. Mix to combine.
Divide sweet potato mixture into potato skin halves. Top with chopped pecan halves and mini marshmallows. Broil until marshmallows are toasted, about 1 minute, being careful not to burn - you want the marshmallows to toast and melt, but not burn. Remove from oven, and drizzle potatoes with remaining maple syrup.
recipe will make 6 halves. This recipe can easily be doubled.