But there is no whisky in this bar snack (6,3)
I believe the answer is:
scotch egg
'bar snack' is the definition.
(a Scotch egg might be eaten in a pub)
I don't understand the remainder of the clue.
(Other definitions for scotch egg that I've seen before include "It is enclosed in sausage meat" , "Savoury snack" , "One cased in sausage meat" , "Hard-boiled item in sausage meat" , "nibble" .)