Have you ever had chestnuts that have been roasted on an open fire? They can be very tasty, but it needs to be done right. Yes, all you need are the chestnuts and roaster (you should have Nat playing as well), but there needs to be a little preparation.
Here's a great article from the site Art Of Maniless to get you started. And no, manliness is not required - or even encouraged. Someone will get burned!