Stir breakfast dish (8)
I believe the answer is:
porridge
I believe this clue is a double definition.
'stir' is the first definition.
(both can mean prison time)
'breakfast dish' is the second definition.
(I've seen this in another clue)
(Other definitions for porridge that I've seen before include "Oat dish; time in prison (slang)" , "Spell in jail and breakfast food" , "Look in the GPO drier for breakfast" , "Possibly breakfast - time in prison" , "Or griped about the dish" .)