Portion of asparagus revolts pet (5)
I believe the answer is:
sugar
'pet' is the definition.
(thesaurus)
'portion of asparagus revolts' is the wordplay.
'SUGAR' is hidden backwards within the letters.
However, I'm uncertain how the hidden word is indicated.
(Other definitions for sugar that I've seen before include "Argus (anag.)" , "Make more palatable" , "Cane or beet product" , "Plantation product" , "White crystalline carbohydrate" .)