Snack at Subway including Japanese dish (5)

I believe the answer is:

katsu

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'japanese dish' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'snack at subway including' is the wordplay.
'including' indicates a hidden word.
'KATSU' is hidden in the letters of 'snack at subway'.

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I've seen this clue in The Guardian.

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