Next, go to Jonette at (G-9) on the middle floor of the Tavnazian Safehold to receive the quest.
The cookbook that she seeks can be found in one of four rooms in the Sacrarium. A ??? will appear on the backside of a bookshelf (not to be confused with the ??? on the desks) at the (F-5)/(F-6) border, (H-5)/(H-6) border, (F-11), or (H-11). Upon selecting the ??? you will receive a Tavnazian Cookbook (Key Item). The ??? will move to another location every 4 hours 15 minutes game-time.
Take the Tavnazian Cookbook back to Jonette in the safehold for your reward.
Note: If you started Promathia Mission 5-3 by talking to Cid you can't start this quest until you reached a certain point in the mission.
Note: If you have already done the quest once, to repeat just talk to Jonette and she will thank you and ask you to bring any other cookbooks you find to her. That will re-activate the quest in your log.