The fried chicken shop near Gongguan is one of the few places that stays open late (most places around Shu Yuan Market close by eleven, but this one is still open at two). The food options are quite similar to other Fat Uncle shops, but this place offers some unique items that you can't find elsewhere, so it's worth trying.
I highly recommend their online ordering system, and you can directly specify your expected pick-up time in the remarks section (though it's still a good idea to allow around ten minutes).
I think the best value at this shop is their chicken bites and fried king oyster mushrooms.
The chicken bites are very generous in portion, although they can sometimes be a bit tough when freshly fried. I recommend asking the owner to season them with pepper for better flavor.
For the king oyster mushrooms, I always choose the original flavor without any added seasonings; they are very juicy and even more cost-effective than regular salty crispy chicken shops.
This is a great option for those not sure what to eat after midnight in Gongguan.