The old Bach perennial. It's not necessarily a Christmas song, but it seems to get played a lot around Christmas time. This is a somewhat simplified version. Feel free to add all the flourishes you want.
I love Baroque music. In fact, I once dreamed of starting an 18th Century Cooking Club. Our motto would be, (are you ready for this?)
If it ain't Baroque...don't fix it! (AAAAAAgh!)