Important quest NPC outside of instance during "Something in the Soup"

Platform: Windows 7
Date & Time: May 11, 2011 15:00 GMT+1
Frequency: Always (However I did not start over the quest to see if it happens again. The mushroom I had to use for it was a pain to get, and I'd rather not have to find a new one!)
Character Name: Efrye Stellaire
Race: Wildwood Elezen
World: Rabanastre
Class/Skill Rank: Culinarian rank 38
Physical Level: 50
Area and Coordinates: Limsa Lominsa (6, 4)
Party or Solo: Solo
Quest Name: Something in the Soup (culinarian's quest for rank 36)
NPC Name: Prudentia

Steps:

1. I completed the quest up to the point where the player has to synthesize a "Foulbelly Meatball". At this point I had to leave the instance in the culinarian's guild to get one of the necessary materials ("button mushroom").
2. After returning to the instance and creating the Foulbelly Meatball, my journal did not update and none of the NPCs within the instance had anything new to say. Opening the map from my journal still points me at the culinarian's guild though, even though there's apparently nothing to do there.
3. Going from the story of the quest, I'll probably have to speak with Prudentia, however she only appears inside of the instance and is out of reach. If I go near her, I leave the instance and she disappears.
4. Here's a screenshot of the situation: http://npshare.de/files/20013fd3/Capture.JPG

I'll help you out with this one cause I remember doing it recently myself. If you read what the NPC asked you to do overall, it is to replace the soup stock which was tainted and to do so you would need a Foulbelly Meatball. After making the Foulbelly Meatball, you continue another synthesis with the meatball and the additional NPC ingredient which was given to you during the instance to make the soup stock. The journal should update at this point and you can continue to finish the quest. But you are correct in saying there is no journal update after the creation of the meatball saying you should now make the soup. SE seems to have forgotten this step in the process and it causes a bit of confusion on what to do next. Enjoy the ending, it's at least more memorable compared to some of the other class quests.

Oh, thanks for the help!

I didn't actually have to create the soup stock though. I just had to make a devilbelly meatball out of the foulbelly meatball and speak to Prudentia afterwards. Still, that part of the quest was kinda confusing. Especially having Prudentia stand there out of reach and the journal insisting that I have to speak to the NPCs in the culinarian's guild. I guess I could've figured it out if I had just tried a little harder though...

IT seems like you were able to resolve this, which is great news! I'm glad that you could get some help to progress with the quest and continue the game.