I'm embarrassed that I never thought of this before, seeing as I've spent most of my adult life as a chef. blush I have been looking at DIY Billy Cans and stainless canteen cups and it finally hit me- the perfect vessel would be a commercial duty bains marie! They're all stainless, NSF certified for food and generally very heavy duty. Fortunately there are two large restaurant supply stores within five minutes of my house. Next time I have a weekday off I will have to check them out.
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“I'd rather have questions that cannot be answered than answers that can't be questioned.” —Richard Feynman