An idea I found and plan on stealing from another site is to use the heavy aluminum disposable baking pans for your kit. The heavy duty pans do not spring leaks even after several foldings (so I've read)and they fold very compactly. ...
sak, could this be what you are refering to?
Dirttime Forum Remember to make the mod of folding the bottom up twice. This isn't meant to be a heavy duty kit, but one of minimum storage space. Don't tweak the folds when you open it up, and press folds between fingers to re-flatten after use and before storage. I have boiled water in it, and opened it up and flattened it without leaks.
...& it was freely given, so no thievery is involved...