Biscuit with ice cream (5)
I believe the answer is:
wafer
'biscuit with ice cream' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for wafer that I've seen before include "Ice cream's biscuit" , "Very thin 14 Down" , "Communion bread" , "Ice-cream biscuit" , "Ice cream biscuit" .)