Sweet bishop to come out with whisky! (12)
I believe the answer is:
butterscotch
'sweet' is the definition.
(butterscotch is a kind of sweet)
'bishop to come out with whisky' is the wordplay.
'bishop' becomes 'B' (abbreviation for bishop in chess).
'to come out with' becomes 'utter' (I've seen this in another clue).
'whisky' becomes 'scotch' (Scotch whisky is an example).
'b'+'utter'+'scotch'='BUTTERSCOTCH'
(Other definitions for butterscotch that I've seen before include "Brittle, yellow-brown sweet" , "Kind of toffee" , "Type of toffee" , "Hard brittle toffee" , "confectionery" .)