Foil packs are a long time favorite. Basically you can open them and test for doneness and reseal and put them back on the fire.
Many campers start with ground beef and eventually get to chicken, shrimp, and a host of other meats. You will eventually have a good idea about how much time they will take. The main issue is making certain they do not leak. Food will burn if there is a path for the fire.
2017 JayFlight 21QB
2013 Ford F150 SCrew V8
Favorite Book On The Road
Currently Reading Picture of Dorian Gray
Author of Mack Thomas: The Total Beat