Kerr's liking the source of Xmas treat (4,7)

I believe the answer is:

kris kringle

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'xmas treat' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'kerr's liking the source of' is the wordplay.
'the source of' indicates anagramming the letters.
'kerrs'+'liking'='kerrsliking'
'kerrsliking' anagrammed gives 'KRIS KRINGLE'.

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

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