DIY solar oven build, my most loyal reader gave me this idea. I tyred this once so I hope it works for her. It's pretty simple to do, and it let's the sun cook for you.
You only need a few things, so let's get started.
With two box's one large one smaller, you want to cut off the top flaps on both. Set them to the side. You will need them later.
Take some foil and glue it into the inside of your boxes. Make sure you are using a non toxic glue.
Take your smaller box and place it in the bigger box. Use crumpled newspaper and stuff around the space of the smaller box. Make sure you stuff it in there very well. After that, take your flaps that you cut off and cut them to fit around the center part covering the newspaper. Then you will glue it down tightly. Now you should be able to see the inside of your small box.
Now you will cut a piece of cardboard to fit in the bottom of your small box. Cover that with foil and spray the foil side with a non toxic black spray paint. When dry you can place it in the box with the painted side facing up. This piece is replaceable if it gets spills on it.
Now take another piece of cardboard and cover that also, but only on one side. This is your sun catcher. On each side of the hinges glue on the sides. A hot glue gun works best for this. You will glue the hinged piece to your bigger box, this should fit over the bigger box and the smaller box serving as the lid.
Use sticks on the other side of the box as hinges. You want to angle your sun catcher 45 degrees and measure where you want to glue your sticks. After you do that cut your sticks and then glue to the outside of your box. Another thing you can do is use glass between the reflector and the boxes.