Lushui — Chinese master stock — is something you can find all across the country. It might be a bit more concentrated in the south (Cantonese and Teochew-style master stocks are quite famous)… but there’s equally Sichuan-style master stock, Yunnan-style master stock, Henan-style master stock. ‘Stewing meat and tofu for hours in heavily spiced, seasoned liquid’ is one of those good ideas that no Chinese cuisine seems to have a monopoly on.
Lushui — Chinese master stock — noodle, on the other hand is an idea that’s very unique to the Guizhou province.
You can find Lufen — i.e., Master Stock Rice Noodle — joints in pockets, centered around in the cities of Anshun and Qianxi. At first glance from the street, they look similar enough to a Lushui shop you could find in Guangzhou:

And just like a Lushui shop in Guangdong, what you do is first order up your desired smorgasbord of stewed stuff: pork belly, tofu jerky, hotdog, whatever.
But in these Guizhou shops, the stewed meat and such acts as the add-ins for the soup — after snipping them up, the vendor then proceeds by simmering rice noodles in the master stock itself. The bowl’s then finished with a big scoop of the master stock as the ‘soup’, and hit with an (optional) spoonful of a unique local chili topping.
It's just… a really smart evolution of the concept of the ‘lushui shop’. Predicting trends is always a fools errand, but with Guizhou food becoming increasingly popular in Shanghai and Shenzhen these days, it wouldn’t surprise me if this concept ended up having some reach.
It’s a great noodle soup; I heavily recommend giving it a whirl.