I am absolutely no authority on these dumplings, but they are the mainstay at this rather new shop at 624 Clement Street. Dumpling makers work in the window.
Everything that I’ve brought home from this shop has been fresh and delicious. I sometimes serve their small pork and cabbage dumplings as living room hors d’oeuvres in small bowls with spoonful of sauce + small fork.
That shop is a couple of years old now 
there are a few tables there that you can eat at, however most of their business is takeout. The XLB are already cooked, we live fairly close by, so we just eat it when we get home
Their radish cake is also quite delicious and so is their beef pancake
Thanks for the update. I’d done a little searching and saw that it’s a few years old. I have a bias against dim sum places that have XLB. Unless ordered, rather than on a cart, IMO they’re subpar.
The XLB out there is mediocr, IMO. Nothing great, but not a bad snack at that price (i think 6 XLB for $4)