Pastry not very short, value doubtful (3-2-4)
I believe the answer is:
vol-au-vent
'pastry' is the definition.
(vol-au-vent is a kind of pastry)
'not very short value doubtful' is the wordplay.
'very short' becomes 'v' (abbreviation; 'short' indicates an abbreviation).
'doubtful' is an anagram indicator.
'not'+'v'+'value'='notvvalue'
'notvvalue' is an anagram of 'VOL-AU-VENT'.
(Other definitions for vol-au-vent that I've seen before include "Puff-pastry savoury" , "Small puff pastry case with savoury filling" , "Light, filled pastry shell" , "Small puff pastry with fish or meat" .)