Snack making seagull soar off (7,4)
I believe the answer is:
sausage roll
'snack' is the definition.
(I've seen this before)
'seagull soar off' is the wordplay.
'off' indicates an anagram.
'seagull'+'soar'='seagullsoar'
'seagullsoar' with letters rearranged gives 'SAUSAGE-ROLL'.
'making' acts as a link.
(Other definitions for sausage roll that I've seen before include "Savoury of minced meat wrapped in pastry" , "Party fare" , "Party nibble" , "party food" , "Cylindrical snack" .)