A few months ago we bought a holiday house in Groot Brak Rivier and I decided to build a sun oven to use while sitting in the sun with a beer. In the pictures below you can see how I bent and riveted aluminum to create the business end of the oven. The idea is to reflect all the sun rays on to a black casserole type dish to create a truly eco-friendly slow cooker.
Before building the base I tested the contraption my cooking a curry amongst the herbs and chillies in our herb garden. Even this red le Creuset casserole absorbed enough energy to cook a beautiful Madras.
I then built a base for it from bits of scrap plywood.
In the pictures below you can see it in action at our beach house. The oven is closed with a sheet of glass or transparent perspex to limit air movement.
Over this past December (2013) holiday, I cooked a leg of lam from scratch in it.