You beat me to posting about this, Vioburn!!
Here's a picture of a solar oven, in case no one's ever seen one:
It shows someone cooking a roast!! And here's the recipe:
1 lean beef chuck or similar roast- about 3 lbs- cut the meat into 2 or 3 chunks-
put the roast into a black pot ( I use "Granite Ware") use whatever you have in the way of a dark pot or you can even use an oven cooking bag set into a pan or skillet.
Empty one package of dry onion soup mix over the meat, cover, and cook in the solar oven for 4 to 6 hours or until tender. You won't believe how good this is! Remember, you can vary this recipe with any thing that you like. I used this example because it is the simplest. The oven can be 200 to 250 F.
This is just ONE of many varities of solar ovens that I've seen. This one seems to be tilted towards the sun, which makes sense, but I can't really see if it has a glass cover on it or not. Some that I've seen do - to help keep the heat in.
One thing about solar cooking - you can't be any kind of hurry!!
Cooking a meal in this way takes planning. But I hear that food cooked slower like this (as would food being cooked in a crock pot) just tastes so GOOD!! It makes sense because none of the flavors are really cooked out of it, because it's cooking so slowly.
I've never made a solar oven, but I have plans to!
All you really need is a sturdy cardboard box, some layers of newspaper, some tin foil, some good tape (reflective tape works best), and preferrably a glass cover of some sort.