Warning: This may not be for everyone: http://gossamergear.com/wp/stoveless-camping-crotch-pot
‘This third option between stoves and no-cook is the brainchild of Gossamer Gear founder Glen Van Peski. Infrared images of the human body confirm what is basically common knowledge; one of the hottest parts of the human body is the crotch area. Your body naturally generates significant heat while hiking; why not harness this heat for a warm dinner…Glen has used this system for years, and we finally talked him into exposing it to the rest of us. The Crotch Pot™ is constructed of ultralight cuben fiber, and attaches to any pants with belt loops. If your favorite pants don’t have loops, just use some safety pins to attach the pouch. Any recipe that you pour hot water into and let stand will work.’
‘Rambling Hemlock’ has some other excellent stoveless cooking ideas. Hers do not involve anything as unsavory as the above: http://ramblinghemlock.blogspot.com.au/2015/02/beginners-guide-to-going-stoveless.html Too many people neglect cold food as a three meal a day option though many have a cold breakfast and lunch.