As has been noted in another thread, there's a story-line problem when you have the early cooking quests, but no information on where buns come from. I eventually sort of "gave up " on that quest and many levels later, added to my cooking skills and was able to complete it.
(There was a similar roadblock for me on another skill tree, but now I can't remember what that one was.)
Suggestions (some made before in other threads):
1. Don't assign quests that can't be completed with the newly acquired skill
2. Make sure that the items needed can be acquired SOMEWHERE in the game, even if pricey or rare
3. Have a hint mechanism, which might be free from the rock or might be something like a seer that you pay for.
But I'm thinking this sort of thing might have been just sort of a mistake, as fewer things are now available from vendors, and maybe the quests didn't get adjusted to match.