I believe that there is a problem with the current set up for confectioner skills which doesn't allow experience gain for "preparation" of items. This is exactly the opposite of how the other craft schools work.
An outfitter gains experience if a flax spool or hide strip is made while an outfitter. In fact, Johald gives a quest to teach you how to distill. If cedar hide tannin is made while an outfitter, outfitter experience is gained.
A blacksmith gains experience if a bronze bar, cedar board or sandstone block is made while a blacksmith.
All of these are examples of "preparation", why should preparation be treated differently for confectioner?
If slicing fruit is considered to be only preparation and not cooking, then the forms for "preparation" should be sold on Gatherer trainers and not Confectioner trainers.
I suggest that the Confectioner experience be fixed to be consistent with the other craft schools.