Throw beef broth, gelatin, anise, cloves, cinnamon sticks, salt, pepper, fish sauce, apple cider vinegar and beef shank in a stock pot. Bring to a boil over high heat, then reduce heat to medium low. Skim the layer of debris off the top. Maintain a light simmer.
While simmering preheat the oven to 350F and place the onion, ginger and garlic on a baking sheet. Bake whole for 15 minutes.
When done cut the onion and garlic cloves in half and slice the ginger into 1/4 thick slices. Add to stock pot. Continue to simmer for 2-3 hours.
Taste your broth, if necessary season with some apple cider vinegar or fish sauce. Allow the broth to cool and skim the fat off the top. Try not to remove all the fat. Reserve what you have removed. The broth can be used immediately refrigerated for up to four days or frozen for up to a month.
Return the broth to the stockpot with the beef flank. You may have to cut it in half, but make site is submerged. in an anise pod for good measure. Bring to a low boil over medium heat. Cook the meat for 30-45 minutes. Depending on your doneness preference. The frozen meat allows to you get really rare beef while still allowing the out layers to soak up some flavors from the broth. If you don't like rare meat, defrost your beef first.
Prepare your toppings
When the beef is done remove from the stock pot and allow to rest for about 15 minutes. You can allow your broth to still cook, but check your flavor at this point. If it needs more salty, that's where the fish sauce comes in. Acid? A dash of lime juice or apple cider vinegar may help. Could use a little more sweet? Throw in a tbsp of brown sugar or agave nectar.
While you're waiting cook your rice noodles according to the package. Remove and coat with sesame oil to prevent sticking.
With a sharp knife cut your meat as thin as possible. If it's too rare a little time in the hot broth will remedy that for you.
Set out the noodles broth beef and toppings for the diners.
You start with noodles in the bowl.
Then throw in some broth, followed by meat, toppings and sauces.
Now slurp away
