A bit of bacon, as always possessing such sound quality (5)
I believe the answer is:
nasal
'possessing such sound quality' is the definition.
(as in a nasal-sounding voice)
'a bit of bacon as always' is the wordplay.
'a bit of' indicates a hidden word (I've seen 'a bit' mean this (the answer is formed by a bit of the clue)).
'NASAL' is hidden within 'bacon as always'.
(Other definitions for nasal that I've seen before include "Of noses" , "front piece of helmet" , "Pertaining to the nose" , "Nosey" , "pinched" .)