Okay, I have tried several things. I can get up to 200', if I am lucky 220', then the clouds come out and it looses it's heat. I have tried boxes, it got up to 220'. But the clouds came out and it didn't sustain it's heat. I tried a bowl, it got up to 140', not hot enough to cook. I tried a fish tank on a black board. It got up to 180', not hot enough to cook. I am trying a cast iron skillet in a cooking bag inside a circle of sun shields out of a car windshield. It has gotten up to 200' but, again, the clouds came out and it has lost temp. I have gotten some more boxes, I am painting them today. I am going to try it one more time. I am beginning to think that in NC it is just not going to sustain the sun long enough for me to cook something this way. I will post next time and let you know how it went.