This is not a particularly serious question so I put it here instead of GQ. It’s certainly pointless.
I need a bag or bags. You know the size of bag you carried your lunch in? Like that or a little bigger. It’s got to dissolve in 100°F (37°C) water. It must be edible.
“What for?”, you ask.
I want to put cut up potatoes, carrots, and celery in the bag. Maybe some sliced mushrooms too. And onion and garlic powder. And some bay leaf and thyme. And put them all in the bag.
There is edible rice paper, but it would dissolve in colder water, too–including the water from cut vegetables. You might need to forget lunch bags and go with an old-fashioned metal lunch box, but made out of gallium.