Place the beef in a pot and enough water to cover. Bring to the boil and then drain the water, rinse the beef with cold water to remove any scum. Set the beef aside.
In the same pot add a good glug of oil and add the onions and cook until softened. Then add the garlic, ginger, Shaoxing wine, sugar, star anise and fish sauce and cook until fragrant. Return the beef to the pot, cover with water and simmer for 90mins. Remove the meat and set aside. Season the stock, add the noodles and cook until just soft.
To serve add meat to a bowl, together with noodles, a few ladles of stock and top with spring onions.