Ginger cookie (4)
I believe the answer is:
snap
'ginger cookie' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for snap that I've seen before include "on the spur of the moment" , "Break - children's card game" , "Break suddenly with cracking sound" , "Simple card-game" , "game of cards" .)