Tonkotsu ramen

Step 1: Put 2 ¼ lb pig's trotters and 3 ⅓ lb pork neck or back bones in your largest pot (8 litres or more), cover with cold water and bring to the boil over a high heat. Boil for 10 minutes; a thick brown scum will rise.

Step 2: Drain into a colander and rinse each piece under cold water, scrubbing off scum and dark clots of blood. Wash the pot. This step decides whether the soup smells clean or porky.

Step 3: Return the bones to the clean pot with 18 ¾ cups water and bring to a rolling boil over a high heat. Keep it boiling hard with the lid half on. Common mistake: turning it down to a gentle simmer. Only a fierce, rolling boil shakes the fat and gelatine into an emulsion; a simmer gives you a clear brown stock instead of a milky one.

Step 4: Boil for about 10 hours, topping up with boiling water from the kettle every hour or so to keep the bones just covered. Scrape the bottom with a wooden spoon each time so nothing catches and burns. Never leave the pot on the hob unattended or overnight; you can split the boiling over two days, chilling the pot in between.

Step 5: While the broth boils, roll 1 ⅓ lb boneless pork belly up tightly from a long side and tie it with kitchen string every 3 cm. Heat 1 tbsp vegetable oil in a heavy casserole over a medium-high heat and brown the roll on all sides, about 8 minutes.

Step 6: Add ½ cup soy sauce, 3 ½ tbsp mirin, 3 ½ tbsp sake, 1 tbsp sugar and 1 ¼ cups water. Bring to a simmer, cover and cook over a low heat for 2 hours, turning the roll every 30 minutes, until a skewer slides in with no resistance. Mirin and sake contain alcohol; for an alcohol-free braise, replace them with 100 ml water and 1 extra tbsp sugar.

Step 7: Lift the chashu out, let it cool, then wrap it and chill for at least 2 hours so it slices neatly. Pour the braising liquid into a jug, cool and refrigerate within 2 hours. It becomes both your egg marinade and your tare.

Step 8: Boil 4 eggs for 6½ minutes, cool in iced water and peel. Mix 100 ml of the cooled braising liquid with 100 ml water in a small bag or tub, add the eggs and refrigerate for 4–12 hours. For anyone pregnant, very young, elderly or with a weakened immune system, boil the eggs for 9 minutes instead.

Step 9: For the last hour of the broth's cooking, add 1 onion, 1 head garlic, 1 ¾ oz fresh ginger and 4 spring onion green tops.

Step 10: Strain the broth through a sieve into a clean pan, pressing on the bones. It should be opaque, creamy and coat a spoon, and you want about 2 litres. If it is thin, boil it hard for another 20 minutes to reduce. If you're not serving it now, cool it fast, refrigerate within 2 hours and use within 3 days, or freeze.

Step 11: Slice the chashu about 5 mm thick. If you like, sear the slices in a dry frying pan over a high heat for 30 seconds a side until the edges caramelise.

Step 12: Bring the broth back to a full boil. Put 2 tbsp of the braising liquid and ½ tsp of 2 tsp salt into each of four warmed bowls; taste the broth and add more salt if needed.

Step 13: Cook 14 oz thin straight ramen noodles in plenty of boiling water for 45–60 seconds only, as thin Hakata noodles go soft fast. Drain very well.

Step 14: Pour about 400 ml of boiling broth into each bowl, add the noodles and top with chashu, halved eggs, 4 tbsp red pickled ginger (beni shoga), 4 spring onions and 2 tsp toasted sesame seeds. Put 2 cloves garlic on the table for anyone who wants it.