In the 1970’s and 1980’s there were several books the either had characters that did it or promoted it.
Why is there no cooking tray in my new car’s engine bay?
Is it dangerous? (It would be less physically dangerous if there was a specific spot for it.)
Mythbusters has an episode (Food Fables) with Alton Brown where they cook a thanksgiving meal in the engine bay. It went surprisingly well, although figuring out where to put everything and the different cooking temps were tricky.