Scots vomit almost swallowing cold drink in Bonn (4)

I believe the answer is:

bock

'drink in bonn' is the definition.
(strong German beer)

'scots vomit almost swallowing cold' is the wordplay.
'scots vomit' becomes 'boke' (Scottish word meaning to vomit or retch).
'almost' means to remove the last letter (most of the word but not all of it).
'swallowing' is an insertion indicator.
'cold' becomes 'c' (eg on taps).
'boke' with its last letter taken off is 'bok'.
'bok' going around 'c' is 'BOCK'.

(Another definition for bock that I've seen is " Beer".)

I've seen this clue in The Guardian.

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