With alcohol banned by trains, I'm mixing cocktails (3,8)

I believe the answer is:

dry martinis

'cocktails' is the definition.

'with alcohol banned by trains i'm mixing' is the wordplay.
'with alcohol banned' becomes 'dry' (e.g. a dry state in the US).
'by' means one lot of letters go next to another.
'mixing' indicates an anagram.
'trains'+'im'='trainsim'
'trainsim' with letters rearranged gives 'martinis'.
'dry'+'martinis'='DRY MARTINIS'

I've seen this clue in The Everyman puzzle in The Observer.

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