Tuna in foil, newly prepared (9)

I believe the answer is:

yellowfin

'tuna' is the definition.
(yellowfin tuna is a kind of tuna)

'foil newly prepared' is the wordplay.
'prepared' indicates anagramming the letters.
'foil'+'newly'='foilnewly'
'foilnewly' with letters rearranged gives 'YELLOWFIN'.

'in' acts as a link.

(Another definition for yellowfin that I've seen is " Tuna".)

I've seen this clue in The Telegraph.

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