First off you want to char the ginger and onions to bring out toasty flavors! Turn the oven broiler to high and make sure the rack is on the first or 2nd tier. Place the onion and ginger cut-side-up on a baking sheet and drizzle and toss with a little oil. Broil for about about 8-10 minutes, until the tops of the onion and ginger are slightly charred. Remove and set aside.
Lets make the broth! While things are charring in the oven, heat the anise, cloves, cinnamon, cardamom and coriander to a large soup or stock pot over medium-high heat for 2-3 minutes until fragrant. Add in the charred onion, ginger, and stock you're using, and stir to combine. Continue cooking until the broth reaches a simmer. Then reduce heat to a low simmer, cover with a lid, and continue to simmer for at least 30-40 minutes. Strain and discard the onions, ginger and spices. Stir in the fish sauce and brown sugar into the hot broth. Now taste and add more seasoning! taste the broth and add in more brown sugar, fish sauce, or salt as needed. I will taste and add, taste and add several times before it's perfect. Don't forget you will be squeezing over lime juice and stirring in your sauces as well when you go to assemble your bowl.
Meanwhile, as your broth is simmering, cook the noodles separately according to package, make them al dente since they will also be sitting in hot soup. Drain in a strainer, then briefly rinse the noodles with cold water to prevent them from continuing to cook. Toss with just a little oil like sesame oil or any other kind of neutral oil to keep the noods from sticking.
If you are using shrimp, right at the end of your broth cooking, drop your shrimp in for 1-2 minutes until pink. Or you can always cook them on the side but I prefer to just drop them in the broth. You can also use shredded chicken or very thinly sliced beef! If you do beef, freeze it for 20 minutes or so before hand so it's easy to slice very thin. Keep it raw and when you put the hot broth over it will cook!
Now comes the fun part! Add a handful of noodles to each bowl. Then ladle the still-simmering hot broth into the serving bowls. If you're using steak, be sure to submerge the steak completely so that it gets cooked. Top each bowl with lots of cilantro, basil, jalapeño, onion, and drizzle generously with Sriracha and hoisin! Make sure to stir it all together so it flavors the broth and you get goodness in every bite!