It’s a chef’s variety, these Tandanus (9)

I believe the answer is:

catfishes

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'these tandanus' is the definition.
The definition suggests an adverb but the answer is not.

'it's a chef's variety' is the wordplay.
'variety' is an anagram indicator.
'its'+'a'+'chefs'='itsachefs'
'itsachefs' with letters rearranged gives 'CATFISHES'.

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I've seen this clue in the Sydney Morning Herald.

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