On an open gas flame, char the onions and ginger until the skins are blackened. If you don’t have a gas stovetop, then roast in an oven preheated to 180°C for 20-25 minutes. Remove, allow to cool enough to handle, then peel the skins off. Rinse in cold water and set aside.
Dry toast all the spices in a small frying pan for three to five minutes over a medium heat, until aromatic. Take the pan off the heat and leave to cool. Put the spices into a spice strainer (breaking up the cinnamon stick if necessary) and set aside.
Next, prepare the bones and meat. Squeeze the juice of the lemons into a stockpot, throw the lemon halves in and fill with plenty of cold water. Soak the oxtail, marrow, beef brisket, flank and ribs and bones in the water, then add the salt. Stir well and leave for one hour.
Discard the lemon halves and set the pot over a high heat and parboil the bones and meat for five minutes. Drain, rinse in cold water and leave to dry.
Rinse the pot used for cleaning the bones and meat and fill with eight litres of water. Add the par-boiled meat. Blast at extremely high heat for three to four minutes to force all the impurities to the surface, then skim off the scum until the water looks clear. Reduce the heat to low, partially cover with the lid and simmer for three hours.
Add the prepared onions and ginger along with the daikon to the broth along with 120g of salt. Stir in the sugar, then continue to simmer for a further 2 hours. Carefully remove the daikon and onion from the broth, add the spice strainer along with the fish sauce. Cook for a further three hours.
Taste and adjust the seasoning to your preference. In the north of Vietnam pho is a little saltier, and in the south it is a little sweeter.
Take the pot off the heat, remove the bones and meat, and allow to cool. Skim off any fat that has risen to the surface, then carefully and slowly strain the broth through a large sieve into a clean stockpot. Don’t rush this process if you want to produce that signature clarity to the broth.
Soak the noodles in a bowl of cold water for 30-45 minutes. Drain and set aside.
For the meat, debone and tear the brisket meat into strips. Cut the flank into thin slices. If you like, tear the meat off the ribs, or serve it on the bones.
Bring a saucepan of water to the boil, then blanch the bean sprouts for five to ten seconds and drain. Divide the bean sprouts between serving bowls.
Fill the pan with fresh water and cook the soaked noodles for three to five seconds, then drain and add to the bowls with the bean sprouts. Add the assortment of cooked meat, then arrange the slices of topside steak on top.
Bring the broth to the boil and ladle between bowls. Add the marrow to the bowls, or leave on the side for guests to help themselves. Finish with the herbs and serve with lime wedges and sriracha and hoisin sauces for dipping the meat (don't add these sauces straight into the broth). Finally, enjoy – you deserve it, chef.