"We like to make soup or a pot of beans in the crock-pot or the clay oven and sometimes we use our sun-oven. These are three valuable items for the do-it-yourself small-scale, whole food homesteader. A sun-oven is an amazing piece of low-tech ingenuity. It will cook almost anything without the use of any fuel other than pure sunlight. We've used it to bake cookies, rice, soup, beans, vegetables and pizza. We've also used it to purify water."

from Kevin and Donna's The Subtle Way And Its Power

Foil-lined cardboard box, black pan, glass pane, reflectors. Use what you have, including your imagination. You'll be amazed!