Greek cuisine staple (4)
I believe the answer is:
feta
'greek cuisine staple' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for feta that I've seen before include "Eastern Mediterranean cheese" , "Greek salad cheese" , "Salty goat or sheep milk cheese" , "Type of cheese" , "Greek cheese from goat or sheep milk" .)