Plan to bring huge pastries over (9)
I believe the answer is:
stratagem
'plan' is the definition.
(stratagem is a kind of plan)
'huge pastries over' is the wordplay.
'huge' becomes 'mega' (mega can mean very large).
'pastries' becomes 'tarts' (tart is a kind of pastry).
'over' says the letters should be written backwards.
'mega'+'tarts'='megatarts'
'megatarts' in reverse letter order is 'STRATAGEM'.
'to bring' acts as a link.
(Other definitions for stratagem that I've seen before include "A cunning plan or piece of trickery" , "Ruse" , "Clever scheme" , "Cunning manoeuvre" , "Cunning plot" .)