I belong to several solar cooking message boards.  Recently one of the boards had a debate going about how to cook potatoes in the solar oven.  Some people were trying to bake potatoes, and not having much luck.  Others said it could be done, but the potatoes came out more steamed than baked.  I decided to give it a try.  I had made this attempt before, but the sun was lost to clouds that day.  On Sunday, I made another attempt.  After washing the potatoes, I wrapped them in aluminum foil — just like for the regular oven.  Then,  I wrapped the potatoes in a piece of black cloth from my sewing room.  The potatoes cooked for three hours. They were hot and about 3/4 done — light and fluffy and delicious.  Another hour would have cooked them all the way but it was supper time and the steaks were ready.  Baked potatoes — another success.