But I can't come up with a definition for munting, so I'll presume it's Kiwispeak for mangling or some other transitive verb indicating you've crushed your little aluminum foil pot.
I'm not sure, other than after a comic pause saying, "Very carefully." It would probably need to go inside something rigid (a bowl, your "other" cookpot?) or have something carefully packed inside to fend off the other packed items.
Shaving those last few possible grams is a real challenge; ask NASA.