Getting quite drunk with ales ruins cocktail (7,7)
I believe the answer is:
tequila sunrise
'cocktail' is the definition.
(I've seen this before)
'getting quite drunk with ales ruins' is the wordplay.
'getting quite' becomes 'tequi' (I can't explain this - if you can you should give a lot more credence to this answer).
'drunk' indicates an anagram.
'with' says to put letters next to each other.
'ales' put next to 'ruins' is 'alesruins'.
'alesruins' is an anagram of 'lasunrise'.
'tequi'+'lasunrise'='TEQUILA SUNRISE'
(Other definitions for tequila sunrise that I've seen before include "Drink" , "Multicoloured cocktail" , "Cocktail - 1988 American crime film - equaliser units (anag)" , "cocktail's required" .)