[ziggus]

There's a few commercial versions of this idea that combine some sort of insulation with a vacuum container, which increases the efficiency.

https://www.cabelas.com/shop/en/thermos-cook-and-carry-syste...

[jerrycruncher]

There was also an infomercial[1] for a product called "AirCore" in the US a couple decades ago for something similar.

[1] https://www.youtube.com/watch?v=SIIWBvgyvmI