The French are after unusually quiet drink (7)
I believe the answer is:
tequila
'drink' is the definition.
(tequila is a kind of drink)
'the french are after unusually quiet' is the wordplay.
'the french' becomes 'la' ('the' in French).
'are after' is a charade indicator (letters next to each other).
'unusually' indicates anagramming the letters.
'quiet' with letters rearranged gives 'tequi'.
'la' put after 'tequi' is 'TEQUILA'.
(Other definitions for tequila that I've seen before include "Mexican agave spirit" , "Distilled agave drink" , "Liquor made from the agave plant" , "one in the slammer" , "Is there another drink to equal it?" .)