Relish impudence (5)
I believe the answer is:
sauce
I believe this clue is a double definition.
'relish' is the first definition.
(relish can mean a sauce or dressing)
'impudence' is the second definition.
(I've seen this before)
(Other definitions for sauce that I've seen before include "Impertinence; dressing" , "What's ... for the goose is ... for the gander" , "''Hunger is good .....''" , "Meal moistener" , "Moistener for food" .)