I have only come across quirks and trinkets that affect eating during hunger checks and camping but nothing affecting food for healing between battles. To my knowledge all characters can always eat 4 meals after each battle to recover HP. If a hero could pick up a quirk that would enable to eat more (and recover more completely between battles) this could encourage experimenting with new parties and strategies.
It could be something like this:
Weak Stomach – Hero cannot take meals for HP recovery when stressed
Comfort Eater – Hero can take extra meals for HP recovery when stressed
These quirks wouldn’t make food more powerful as a healing item, they would just open up new options for how it could be used to sustain a party.
I would want to test it but I belie any “healing received” quirks actually increase/decrease healing due to eating. It would be easy to test, you could bring a trinket that significantly increases healing received, and eat with it equipped and not.
I like the idea of being able to eat more food with a quirk.
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