Wait, you're trying to cook IN a plastic Nalgene bottle over a stove or an open fire????????? Why???? Seems like subjecting a Nalgene to that kind of heat with water or wet food in it would just release toxic chemicals into whatever's held in the bottle, or just risk melting the Nalgene completely.
My aluminum "billy" pot (converted Coleman coffee pot) weighs less than an empty 1 liter Nalgene already. It's been on hundreds of fires & stoves and still going strong. If I went on a self-support that specifically requires stoves and no open fires, I have an MSR Superfly that fits inside of it along with 2 fuel cells and Lexan utensils. That all fits in a large-sized ziploc to keep the stove dry and protected, with no added weight.
Seems like maybe the new "JetBoil" or MSR "Reactor" style stove/pot systems are the lightest and most effecient ways to go if you either can't have a fire or don't want to try cooking on open fires. Either those, or you go the "Zip Stove" route that Chip posted about, that runs on all kinds of naturally available fuels.
I'm really curious if anybody knows of a river trip that is generally done by self-support kayaks only that prohibits open fires?? (meaning the harder, more remote multi-day runs that are either un-raftable or it's just super difficult to find rafters good enough to run them) Curious to know if there are any.
So many rivers, so little time..........