\When you are slow cooking and building a broth, the best way to keep the broth clear (and not cloudy) is to keep the simmer low and long. I find that this tip is very useful in making noodle soups, especially phở bo (beef pho). I like my beef phở broths to cook somewhere between 12-24 hours, depending on what I’m feeling at the time. How gentle should a low simmer be? You shouldn’t be seeing any bubbles, just a slight murmur of the broth while it is simmering.
