Don't have a roasting pan but dying to try chestnuts over an open fire? We found two secret tricks to try out as an alternative:
ALUMINUM PIE PLATE
Take an aluminum pie plate and punch a row of holes- they don't need to be super tiny but make sure they're not so big that chestnuts might fall through. Slice the surface of the chestnuts in an X shape to prevent the buildup (and explosion) of steam pressure during cooking. Place chestnuts in the pie plate and put it all on the grill over white hot coals for about 15 minutes, stirring occasionally. Peel and enjoy!
"There are various pans and big slotted spoons designed especially for roasting the nuts, with holes in their base to let the flames through. If you don’t have the kit, you can improvise by making some holes in a cleaned tin can with its lid still attached (but pulled back, so you can put the chestnuts in). Quarter-fill the tin with nuts, lever the lid back in place, to seal in the nuts, then put the tin in the fire. Cook for about 15 minutes, turning the can a few times, and they’ll be ready to be peeled and eaten as soon as your fingers can handle the heat."
- From The Guardian