Earl of Desmond near Tralee does it and has music and entertainment not sure how good it is as I have never been though. I am sure there is others in Killarney also
Try Meadowlands hotel in Tralee. Not sure if it will be serving Christmas dinner, but it's a nice hotel and has a cosy atmosphere. The restaurant does lovely food too.
I used a company called Christmas Made Easy
Provide everything you need to produce 4-5 course christmas dinner
If your a foodie its worth checking out
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