I didn't believe it until I tried it. A warm day, direct sunlight and a hot, I mean hot brick it all came together. I was tempted to eat it, but passed, the brick didn't pass for clean exactly. I have cooked some fun stuff-pizza rolls in a camp fire, that was one no one thought would work, but everyone wanted to enjoy, the egg in the back yard was a first. I is not the quickest way to cook an egg, but made for a fun photo.