For a simple poo soup, season with rock sugar, salt and fish sauce.
For those who want a more authentic taste, add a little MSG (monosodium glutamate), also known as the -spice-that Westerners-like-to-hate.
I am also going one step further by adding broth powder. Since I can not find beef broth powder that I like, I just add chicken broth powder to both chicken and beef poo. You can also use mushroom spindle powder, which is available in many Asian supermarkets.
There are several types of rice noodles that you can use for poo noodle soup.
Have the dried rice noodles in the dry aisle that requires boiling. You can buy some of these packages and keep them forever in the pantry.
There are fresh rice noodles (banh pho tuoi / bánh phở tươi) In the cooling passage. These noodles are semi-dry and require quick whitening. This is what I usually get for my poo noodle soup. They are usually sealed in a vacuum cleaner.
And there are those in styrofoam trays that are also marked as fresh rice noodles (banh pho tuoi / bánh phở tươi) But flat and wide and definitely look fresh. Although the label is the same as poo noodles, these noodles are not intended for hot soup, as they break down easily. These are for Banh Uot / Bánh Ướt. They require rapid heating in the microwave or bleach in boiling water. Then separate by hand, strand by strand.
Unfortunately it is not possible to boil faux rice noodles at once in advance like other noodles. You need to do this one serving at a time.