While prepping the meat cuts and vegetable toppings, bring a pot of water to a boil.
Once boiling, put the pork butt and hock in water to blanch/clean. Leave for about 5 minutes on a rolling boil, leaving the lid off. Remove and scrub off any excess gunk after draining. Keep this meat off to the side.
In the same pot, now empty, char the onion for 5 minutes. Add in the star anise after and leave for about 1 minute. Don’t need to add oil here, as the point is to char the ingredients to get a layer of flavor out. Afterwards, add in the garlic, ginger, cinnamon stick and lemongrass stalk (if you have them). Leave for 3 minutes.
After letting the aromatics settle, add back the meat. Cover with 3-4L of water. Add sugar, lime, powders (cinnamon and lemongrass if you’re using those), and chili paste.
Bring to boil, covered.
After arriving at a boil, reduce heat to simmer, uncovered for at least an hour. You can take this time to make the noodles off to the side and adjust cooking time based on the instructions of your noodles (mine take ~15 minutes).
Skim the soup of excess fats and scum at the top. You don’t have to, though. The strainer at the end will get rid of the scum, and oil-wise this is usually fine as well. To your preference.
Right before the soup is done simmering, add pork balls either into the pot or a separate pot to cook. These are often precooked and only need a few minutes to heat back up.
After simmering, take out the meats. Pour the soup through a strainer as you add broth to bowls (or strain the entire pot into a separate pot).
I normally have all bowls lined up, placing the noodles in first, adding all vegetables in after, leaving plenty of chilis, cilantro, onions, and lettuce off to the side as well. Leave lime wedges out of the bowl. Add in meats, and finish off by straining the hot soup into the bowl. Add chili paste or chili oil again at the end.
That’s all! Enjoy the taste of Vietnam with this delicious slurpy stuff in a bowl.