Forbids a cigarette end to be included with the food! (5)
I believe the answer is:
beans
'food' is the definition.
(beans matches up with the definition food)
'forbids a cigarette end to be included' is the wordplay.
'forbids' becomes 'bans' (banning is a kind of forbidding).
'end' says to take the final letters.
'to be included' means one lot of letters goes inside another.
The last letter of 'cigarette' is 'e'.
'bans' placed around 'e' is 'BEANS'.
'with the' acts as a link.
(Other definitions for beans that I've seen before include "Nothing at all in US" , "Coffee seeds" , "Haricots for instance" , "nuts" , "Haricots, e.g." .)