Take one old satellite dish and a pile of CDs for whatever old software you have filling your drawers. Bolt the CDs to the mesh of the dish. You will have a solar stove capable of 425 °C (797 °F). In an earlier experiment CD's covered every available square centimeter of the surface of the dish. It produced over 425 °C (797 °F). More than needed for cooking. Do not try to retrieve anything from the focal area without a leather glove on.