Preheat the oven to 350 degrees F
Spray a 9x13 baking dish with cooking spray. Set aside.
In large stock pot add sweet potato chunks and cover with water. Bring water to a boil, and cook until potatoes are fork tender, about 10-15 minutes. Drain and mash potatoes in a mixing bowl.
5 sweet potatoes
In bowl of a stand mixer (or use electric mixer) combine mashed sweet potatoes, brown sugar, butter, orange juice, and cinnamon.
½ cup packed brown sugar, ¼ cup butter, 3 tablespoons orange juice, 1 pinch ground cinnamon
Spread mixture into evenly into prepared baking dish. Top sweet potato mixture with mini marshmallows.
Bake 25-30 minutes or until marshmallows are golden brown.
1 10.5 ounce package miniature marshmallows