Begin second pastry (5)

I believe the answer is:

start

'begin' is the definition.
('start' can be a synonym of 'begin')

'second pastry' is the wordplay.
'second' becomes 's' (common abbreviation).
'pastry' becomes 'tart' (tart is a kind of pastry).
's'+'tart'='START'

(Other definitions for start that I've seen before include "Begin; flinch" , "Initiate" , "Set in motion" , "open" , "lead" .)

I've seen this clue in The Telegraph.

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