how to make a solar oven 1. Aluminum Foil 2. Cardboard ... be fooled - despite the simple design, this full-power cooker works very well and is in no way "minimum" as far ... should be larger all around, but it doesn't matter how much bigger, as long as there is a half inch ... in the top of the outer box (Figure 1).Decide how deep you want your oven to be. Ideally, it should ...