Soup for one on returning (6)
I believe the answer is:
potage
'soup' is the definition.
(potage is a kind of soup)
'for one on returning' is the wordplay.
'for one' becomes 'eg' (I've seen this in other clues).
'on' becomes 'atop' (I've seen this before).
'returning' shows that the letters should be reversed in order.
'eg'+'atop'='egatop'
'egatop' backwards is 'POTAGE'.
(Other definitions for potage that I've seen before include "Stock food item" , "> sort of liquid nourishment" , "that's thick" , "which is fairly thick" , "French soup, usually thick" .)