Quiche Lorraine ingredient (5)
I believe the answer is:
bacon
'quiche lorraine ingredient' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for bacon that I've seen before include "Francis ---, Ir. painter" , "The meat to bring home for success" , "Salted pig-meat" , "sizzler" , "Salted and smoked pig meat" .)