I always wondered whether heating a piece of metal under a hot sun is enough to get it to cooking temperature.
In scout survival training (or at least from where I'm from), we're taught that if we're stuck in the mountain with some rocky outcrops, you should seek out a nice, flat slab of rock. Leave it out in the sun for a while... Then start cookin'. You can make anything from fried sausages to omelette, provided it's sunny out long enough.
In the Middle East, they actually bake (unleavened flat) bread this way. They just have clay cylinders that heat up in the sun, and they slap bread dough across its vertical surface. (The dough is sticky enough to hang on.)
Don't play around with metal bars in summer.shzzzzzzzzshzzzzzzzzHeyhey, be careful.Whoa! The egg's frying!!So hoooot!!When they're outside for a long time, the metal gets as hot as this.You'll burn your hand.