Island where Brown consumes excellent whiskey (6)
I believe the answer is:
taiwan
'island' is the definition.
(Taiwan is an example)
'brown consumes excellent whiskey' is the wordplay.
'brown' becomes 'tan' (tan is a kind of brown).
'consumes' means one lot of letters goes inside another.
'excellent' becomes 'ai' (resembles 'A1', old-fashioned term for excellent).
'whiskey' becomes 'W' (alpha bravo charlie delta ...).
'ai'+'w'='aiw'
'tan' enclosing 'aiw' is 'TAIWAN'.
'where' acts as a link.
(Other definitions for taiwan that I've seen before include "Island in East" , "Former Formosa" , "Island off mainland China" , "foreign island" , "Disputed island off china, used to be Formosa" .)