Eorzean coookbook, as a real book, I mean. It wouldn't have to contain all the recipes, even not near it. That would be daunting task. But I would love to be able to buy an official eorzean cookbook with a selection of recipes throughout XIV (SB included) that can be prepared in real life. Surely in some cases substituting the fantasy ingredients with more down to earth ones. Finding apkallu eggs might prove hard, and potatoes obviously work well for popotoes etc.
Silly idea maybe, thoughts?