Greatly enjoy sauce (6)
I believe the answer is:
relish
I believe this clue is a double definition.
'greatly enjoy' is the first definition.
(I've seen this before)
'sauce' is the second definition.
(I've seen this before)
(Other definitions for relish that I've seen before include "Gusto" , "Savour and enjoy food." , "what goes on food" , "Sauce or flavouring" , "Sauce; zest" .)