I think M-i-L's calculations for the winter solstice are off by a couple of days. June says the proper way to celebrate dong zhi is to have a clan reunion and have a big feast including tang yuan soup all round.
We marked the occasion tonight according to the Wong family tradition: cook up a hoarde of wo tie dumplings in both deep-fried and boiled varieties, and eat them with a dip comprising fresh chilli padi paste, black vinegar, sesame oil and thin shreds of ginger. Eat until silly. Simple and easy.
The longest night of the year also reminds me that it's only 2 days till Christmas. Really? I haven't been paying attention. Sigh.