Spicy Huế beef noodle soup (Bún bò Huế)

1. Put the beef shank and pork knuckle in cold water, bring to the boil, boil for 5 minutes, then drain and rinse – this keeps the broth clear.

2. Return the meat to the pot with fresh water (3 litres); add the halved onion, charred in a dry pan, and the lemongrass, bruised with the back of a knife and tied in a knot, and simmer gently for 2-2.5 hours until the meat is tender.

3. Mix the shrimp paste with 100 ml water, let it settle and pour only the clear liquid into the broth; season with the fish sauce, sugar and salt.

4. For the chilli oil, gently fry the very finely chopped lemongrass, shallots and garlic in the oil, then add the chopped chillies and fry for 1 minute; stir some into the broth and set the rest aside for serving.

5. Lift out the meat, thinly slice the shank and cut the knuckle into rounds; cook the thick rice noodles and drain.

6. Divide the noodles between bowls, top with the meat, ladle over the hot broth and serve with spring onion, bean sprouts, mint, lime and chilli oil.

Tip: The famous soup of Huế, the former imperial city: punchier than phở, fragrant with lemongrass and spicy. Shrimp paste gives the deep, distinctive flavour – a little goes a long way, and use only the clear liquid once it has settled.