I gave away my solar oven and am in the process of building another. It's not all the way done but I've got it sitting on the chair in the backyard anyway. I'm planning on having an interior box set inside an exterior box (which will help hold in the heat). Right now I just have the interior box built. It's just a cardboard box with foil and glass. I am going to redo it somewhat because the top has a little too much shadowing of the interior.
It's 11:00 in the morning and it's 70° outside. It's almost 200° in the oven. Not bad for an incomplete project. I'll post more pictures soon. I'm hoping to work on it some more this weekend and get it finished.