Work in soup production (4)
I believe the answer is:
opus
'work' is the definition.
(I've seen this before)
'soup production' is the wordplay.
'production' indicates anagramming the letters.
'soup' is an anagram of 'OPUS'.
'in' acts as a link.
(Other definitions for opus that I've seen before include "Composer's catalogue number" , "Major work" , "Artistic work" , "(Numbered) musical composition" , "Soup (anag.)" .)