Fruit cracker (5)
I believe the answer is:
peach
'fruit cracker' is the definition.
'peach' can be an answer for 'fruit' (type of fruit). I am unsure of the 'cracker' bit.
'fruit cracker' is the wordplay.
'fruit' becomes 'pea' (pea is a kind of fruit).
'cracker' becomes 'ch' (I can't justify this - if you can you should believe this answer much more).
'pea'+'ch'='PEACH'
(Other definitions for peach that I've seen before include "Turn informer" , "Inform on" , "nickname of US State" , "Fruit with downy skin" , "Furry fruit" .)