Tonkotsu Ramen

Place the pork bones in a large stockpot, cover with cold water and bring to a rolling boil, then boil hard for 10 minutes to draw out impurities.

Drain the bones and rinse them and the pot thoroughly under cold water to remove all scum, then return the bones to the clean pot.

Cover the bones with 3 litres of fresh water, add half the ginger and garlic, and bring back to a rolling boil.

Boil vigorously, uncovered, for 12 to 18 hours, topping up with boiling water to keep the bones just covered and skimming off any scum every few hours, until the broth turns milky white and thickens.

Meanwhile, rub the pork belly all over with the remaining ginger, garlic, 40 ml of the soy sauce, the mirin, sake and sugar in a separate covered pan, and braise gently on the hob for 2 hours, turning every 30 minutes, until very tender.

Lift the pork belly out, wrap tightly in foil and rest for 10 minutes, then slice it thinly for topping.

Bring a small pan of water to the boil, lower in the eggs and cook for 7 minutes, then cool in iced water, peel and halve.

Strain the finished pork broth through a fine-mesh sieve and stir in the remaining soy sauce and the salt to season.

Cook the ramen noodles in boiling water according to the packet instructions, then drain well.

Divide the noodles between bowls, ladle over the hot broth, and top each with sliced chashu, half an egg, beansprouts, spring onion and torn nori.