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.

In bowl of a stand mixer (or use electric mixer) combine mashed sweet potatoes, brown sugar, butter, orange juice, and 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.