Pre-heat oven to 350°F

Place sweet potatoes in a large saucepan with enough water to cover.

bring to boil, cook until tender, about 15 minutes.

remove from heat, drain,and mash.

Place mashed sweet potatoes in a large bowl

Use electric mixer to blend margarine, brown sugar, orange juice, and cinnamon.

Spread evenly into a 9x13 inch baking dish, top with miniature marshmallows.

Bake for 25-30 minutes in the preheated oven, or until heated through. and marshmallows are puffed and golden brown.