From a 2013 thread, here's what I wrote:

....as a kid, I'd read a book from my grandparents' time or so - Lucy Fitch Perkins' The Cave Twins - and in that book, the children "roast" eggs in the coals of their cave fire. My grandmother let me do this in the fireplace only after we'd wrapped the eggs in foil first, in case of explosions. They came out a bit cracked, but otherwise, much like boiled eggs. It was one of those sentimental adventures.

8/20/13
And in the late Ruth Chew's children's book about two runaways - The Secret Summer, a.k.a. Baked Beans for Breakfast, the kids get the flattest big stone they can find, put it in the fire for a while then take it out, and then (IIRC) they take a slice of bread with a large hole, place it on the stone, crack an egg into the hole, and both the bread and the egg get well-cooked.

Lenona.

P.S. You can read "The Cave Twins" here, with illustrations! The scene with the eggs is in the first chapter - but what's more interesting, IMO, is what foods the grandmother imagines the twins have brought her when they ask her to guess. (That happens right after the picture of the three of them standing by the fire.) In the next chapter, it's explained how you can boil water without a clay or metal pot - to cook bison meat!

https://www.gutenberg.org/files/2842...-h/28425-h.htm

My copy looks like this, except it's deep red:

https://www.ebay.com/itm/1916-The-Ca...-/372019173295