Just remember to always pierce the chestnuts deeply with a fork before you roast them in an oven or microwave — otherwise, they explode and it sounds like a bomb going off! (My teenage boy found that so entertaining one Christmas...) I was cleaning up chestnut mush for days.
The directions I saw said to make make an X-shaped cut on the round side of each chestnut ... the shell actually peels back when they’re done ... they also do not explode!! :-)
https://www.thespruceeats.com/how-to-roast-chestnuts-in-oven-4113870