Ingredient left omen about informant (10)

I believe the answer is:

lemongrass

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'ingredient' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'left omen about informant' is the wordplay.
'left' becomes 'l' (common abbreviation).
'about' indicates an anagram.
'informant' becomes 'grass' (term for an informant or traitor).
'omen' anagrammed gives 'emon'.
'l'+'emon'+'grass'='LEMONGRASS'

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I've seen this clue in The Daily Express.

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