Master barmen's cocktail produces uneasiness (13)
I believe the answer is:
embarrassment
'uneasiness' is the definition.
(thesaurus)
'master barmen's cocktail' is the wordplay.
'cocktail' indicates an anagram.
'master'+'barmens'='masterbarmens'
'masterbarmens' anagrammed gives 'EMBARRASSMENT'.
'produces' acts as a link.
(Other definitions for embarrassment that I've seen before include "Discomposure" , "Financial difficulty; feeling of shame" , "Self-consciousness, shame" , "Financial difficulty -- abundance" , "Awkwardness, discomfiture" .)