Drink that helps make a job rewarding (4)
I believe the answer is:
brew
'drink' is the definition.
(brew is a kind of drink)
'helps make a job rewarding' is the wordplay.
'helps' indicates the answer is hidden within the clue (I've seen 'helping of' mean this (I've seen this in other clues)).
'BREW' is hidden within 'make job rewarding'.
'that' acts as a link.
(Other definitions for brew that I've seen before include "Make, eg, beer" , "Ferment rather than distil" , "A pot of tea?" , "Mixture" , "Plot" .)