Combining Food and Chemistry
So people constantly say that cooking is just chemistry, or chemistry is just more precise cooking, or whatever the eggheads say, so I think it would be really cool to add more crossover between the two systems.
Distilling I feel like could have the most interactions, we already have to distill milk from milk sacks to use in recipes >!or milk sows!<, but what if there was more we could distill and use for cooking, things like making oils from some of the plants we have access to, apple juice from apples that we can then make into cider, meat-based broth to make new soups (or make existing soups better, I'm still sad that ante-juice instead of water doesn't do anything), shadowberry jam, stuff like that.
Additionally it'd be cool to be able to season food with tinctures, eating a pie slice seasoned with a restoration tincture to save on item slots.
I just love both cooking and chemistry and would love to have way more to do with that.