Merlot best in mixed drinks (6,6)

I believe the answer is:

bitter lemons

'drinks' is the definition.
(bitter lemon is a kind of drink)

'merlot best in mixed' is the wordplay.
'mixed' indicates anagramming the letters.
'merlot'+'best'+'in'='merlotbestin'
'merlotbestin' is an anagram of 'BITTER LEMONS'.

I've seen this clue in The Guardian.

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