Just about every recipe for Canelé Bordelaise says traditional molds (of tinned copper) must be pre-seasoned by coating the inside with beeswax and fat and heating at about 350°. That's much lower than the temperatures used to season cast iron—and good thing, because tin has a low melting point! But does this do any good?
Are they truly applying some type of seasoning (i.e., a durable, non-stick coating of polymerized fat), or is it just multiple layers of grease, to make sure the caramel doesn't stick?
Janet
I think its just to melt the fats/wax to build up a layer or 2... Beeswax melts at just over 60°C - the 170°C you suggest is below the flash point though (about 200°C)
While beeswax is traditional, I use a commercial spray release: http://www.deco-relief.fr/product.php?id_product=9839&id_lang=1
Don't have "proper" copper moulds though - maybe one day!
-Gordon