Shanghai 上海 - 佳家汤包 Jia Jia Tang Bao

佳家汤包 - I felt it is 5 times better than Nanxiang XiaoLongBao. And cheap too.
Can see the long queue despite the rain :)

The long queue is worth the wait.
But the shop is really small, so you may have a hard time finding a place to dine in.