So I see this issue but I don't see anything in questie...

I'd like to see vendors that have recipes for sale. They aren't always obvious as sometimes general/trade vendors have cooking recipes but cooking vendors don't or only certain ones do.

It might also be interesting to show them as unfinished, track recipes, once the profession has be added and not all recipes that vendor sells have been acquired.

note: this might also work as "interesting items for sale" which just noticed

That is totally something that can be achieved, when going through the Questie database. But also not something that is a core functionality wanted to be in Questie. You could even made a small extra addon, using the Questie database.