As an introduction, my wife, Denise, and I have been playing with solar cookers and ovens for awhile. Denise built a wooden one with a shop teacher, many years ago, when she was a Home Economics Teacher in Switzerland. The inside of the box was painted black. It worked well and the students had fun with it. We built one of the ovens from a cardboard box with the glass in the top, but it just wasn't durable. We also have two "Hot Pot" solar cookers and we really like those. If you are intereste