Blended mince pie with rum (6)
I believe the answer is:
impure
'blended' is the definition.
(blended rather than pure or unadulterated)
'mince pie with rum' is the wordplay.
'mince' is an anagram indicator.
'with' is a charade indicator (letters next to each other).
'pie' after 'rum' is 'rumpie'.
'rumpie' with letters rearranged gives 'IMPURE'.
(Other definitions for impure that I've seen before include "Adulterated, tainted" , "Adulterated or unchaste" , "Sullied or adulterated" , "Dirty or immoral" , "Tainted, not chaste" .)