Blunt possibly in raising flatbread expertise (7)
I believe the answer is:
traitor
'blunt possibly' is the definition.
(Antony Blunt was a spy for the Soviet Union)
'raising flatbread expertise' is the wordplay.
'raising' is a reversal indicator.
'flatbread' becomes 'roti' (type of flatbread).
'expertise' becomes 'art' (I've seen this before).
'roti'+'art'='rotiart'
'rotiart' reversed gives 'TRAITOR'.
'in' acts as a link.
(Other definitions for traitor that I've seen before include "One committing treason" , "defector?" , "Rat displayed" , "Rat riot (anag.)" , "Double-crosser" .)