Food that's revolutionary planted by east Kent area (6)
I believe the answer is:
cheese
'food' is the definition.
(cheese is a kind of food)
'revolutionary planted by east kent area' is the wordplay.
'revolutionary' becomes 'che' (Che Guevara the Marxist revolutionary).
'planted by' says to put letters next to each other.
'east' becomes 'e' ('E' can be a synonym of 'east').
'kent area' becomes 'se'.
'che'+'e'+'se'='CHEESE'
'that's' acts as a link.
(Other definitions for cheese that I've seen before include "Gloucester or Edam, say" , "Nautical cap worn without badge" , "A big one would be important" , "Caerphilly" , "Dairy food; VIP" .)