Brandy butter sent back cold (4)
I believe the answer is:
marc
'brandy' is the definition.
(marc is a kind of brandy)
'butter sent back cold' is the wordplay.
'butter' becomes 'ram' (I've seen this before).
'sent back' is a reversal indicator.
'cold' becomes 'c' (eg on taps).
'ram' in reverse letter order is 'mar'.
'mar'+'c'='MARC'
(Other definitions for marc that I've seen before include "Sort of brandy made from the remains of pressed grapes" , "Type of brandy" , "Drink" , "A brandy; --- Chagall, artist" , "Chagall for one" .)