A vehicle working in motorway food (8)
I believe the answer is:
macaroni
'food' is the definition.
(macaroni is a kind of food)
'a vehicle working in motorway' is the wordplay.
'vehicle' becomes 'car' (car is a kind of vehicle).
'working' becomes 'on'.
'in' is an insertion indicator.
'motorway' becomes 'mi' (resembles M1, English motorway).
'a'+'car'+'on'='acaron'
'acaron' put within 'mi' is 'MACARONI'.
(Other definitions for macaroni that I've seen before include "Pasta in long tubes" , "A Minorca kind of pasta" , "Long thin pasta" , "Omani car (anag)" , "Type of pasta" .)