Preheat oven to 375F and grease 9x9 dish. Alternatively use a 9x13.
Peel and chop sweet potatoes in 1/2 inch rounds. Add sweet potato rounds to dish.
In a saucepan, heat butter over medium-high heat. Once melted, add sugars, orange juice, cinnamon, salt, ginger, cloves, and nutmeg. Stir until boiling. Once boiling, reduce heat to medium and let cook an additional 5 minutes or until syrup has thickened slightly. Turn off heat.
Pour syrup over sweet potatoes and coat each potato as best you can.
Cover with foil and bake 30 minutes. Take off foil and baste sweet potatoes with syrup. Bake another 50-55 minutes uncovered. Baste with sauce every 15 minutes.
Add marshmallows with 10 minutes left. Let cool slightly before serving!