From now on fetch heron for cooking (10)

I believe the answer is:

henceforth

'from now on' is the definition.
(synonyms)

'fetch heron for cooking' is the wordplay.
'for cooking' indicates an anagram.
'fetch'+'heron'='fetchheron'
'fetchheron' is an anagram of 'HENCEFORTH'.

(Another definition for henceforth that I've seen is " From now on".)

I've seen this clue in The Times.

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