You can pick broad soft white noodles or chewier, thin egg noodles. I chose the egg noodles and the bowl of noodle soup comes with generous slices for duck and whole mushrooms in a delicious broth...all for around $5!
There's two locations for Bo Ky, though I would stick with the original location on Bayard St.
80 Bayard St
(near Mott and Mulberry)