In a medium saucepan add beef, ¼ cup soy sauce, oyster sauce, brown sugar, garlic, ginger, star anise and half the beef stock. Bring to a boil, regularly skimming impurities off the top, and simmer, uncovered, for 1 ¼ to 1½ hours or until the beef is tender and liquid reduced and thickened. Drain off most of the liquid and set meat aside, covered with foil to keep warm. Shred meat once cool enough to handle.
In a large saucepan add remaining beef stock, 1 cup (250ml) water, miso paste, remaining soy, mushrooms, pak choy and snow peas. Heat over medium-low, covered, for 5 minutes or until pak choy and snow peas are tender.
Meanwhile, cook eggs for 4 to 5 minutes in a medium saucepan of simmering water. Remove with a slotted spoon and place in a bowl of cold water. Once cool enough to handle peel eggs and cut into halves.
In the same pan of boiling water cook noodles according to packet instructions. Drain.
Divide noodles among bowls and ladle miso soup and vegetables over the top. Add beef mixture and eggs to bowl. Serve sprinkled with sesame seeds, coriander, chilli and Sriracha sauce, if desired.
The beef mixture can be used on noodles, Asian tacos, or served with rice and green vegetables.
Use any Asian mushroom or Asian green vegetable of your choice in the miso soup.
You could serve the soup with numerous accompaniments – green onions, Asian pickles, crispy shallots.