I saw this idea online and although I used the same ingredients I made a much smaller batch. They turned out perfectly and were a hit at my Aunt's Thanksgiving Feast. I will definitely make them again. The hardest part was making the orange bowls, but that wasn't hard so much as a tedious. I have never been a fan of sweet potatoes or yams (didn't even know they were two different things before) but I did like this and wanted more when I finished mine.
2 large sweet potatoes
2 large yams
1/4 cup orange juice
2 tbsp. orange juice concentrate
2 tbsp. honey
1/4 cup butter, melted
1/2 tsp. cinnamon
Cut 6 oranges in half and remove the meat of the orange, creating 12 hollow bowls. Fill a 9x13 glass baking pan with all the bowls. Peel sweet potatoes and yams and cut into chunks, boil for about 15 minutes or until tender; drain and mash until very smooth. Blend the orange juice, OJ concentrate, honey, butter and cinnamon; stir into the bowl and and mix well. Fill each orange bowl with the yam/sweet potato mixture. Put one marshmallow on top of each. Put the pan in the oven for 20 minutes or so til the marshmallows start to melt and turn brown.