Vietnamese Bún Bò Huế (Spicy Beef Noodle Soup from Huế)

Place the beef shank and pork knuckle in a large stockpot and cover with cold water. Bring to a vigorous boil over high heat and boil for 5 minutes. Drain, discard the blanching water, and rinse both the pot and the meat under cold running water. This blanching step purges the proteins and blood that would otherwise cloud and bitter the broth. The rinsed meat should be visibly clean, with no grey foam adhering.

Return the meat to the cleaned pot. Add 3 litres of cold water and bring to a boil, skimming any further foam that rises. Add the 6 bruised lemongrass stalks and the 3 whole fresh chillies. Reduce to a steady, gentle simmer — the surface should tremble rather than roll — and cook for 3 to 4 hours, until the beef shank and pork knuckle are fully yielding when probed with a chopstick or skewer. The broth will be opaque and pale gold, carrying the fat released from the pork knuckle.

Meanwhile, dissolve the 30 g of mắm ruốc for the broth in 125 ml of cold water. Allow the solids to settle, then carefully pour off and reserve the upper liquid, discarding the sediment. Set aside.

Prepare the shrimp paste oil: warm 60 ml of neutral oil in a small saucepan over medium heat. Add the finely minced lemongrass from 3 stalks and fry, stirring, until fragrant and just beginning to colour — the kitchen will smell sharply of cooked lemongrass. Add the 20 g of mắm ruốc and fry, stirring constantly, until the paste darkens to a deep brick-red and the oil takes on its colour, 2 to 3 minutes. Remove from the heat. The oil should be vivid red-orange; the minced lemongrass suspended throughout it. Set aside.

When the meat is cooked, lift the beef shank and pork knuckle from the broth. Slice the beef shank across the grain into portions. Pull or chop the pork knuckle meat into serving pieces. Strain and discard the lemongrass and chillies. Return the broth to a simmer. Stir in the strained mắm ruốc liquid. Season with fish sauce, tasting as you go — the broth should be deeply savoury, faintly fermented, and distinctly spiced from the simmered chilli.

This is where the dish lives or dies. Ladle the finished broth over the drained bún noodles in each bowl and arrange the sliced beef shank, pork knuckle, and chả lụa over the surface. Then spoon the shrimp paste oil generously over each bowl — it must be added in sufficient quantity for the deep red-orange colour to bloom across the broth and for the fermented, lemongrass-sharpened aroma to assert itself immediately on approach. Added in too small a quantity, the bowl is beef broth over rice noodles. Added correctly, the preparation's full complexity — the fermented depth of the mắm ruốc, the aromatic sharpness of the fried lemongrass, the heat of the chilli — appears at once and the bowl is recognisably, unambiguously bún bò Huế.

Serve immediately, with a separate plate of drained shredded banana blossom, picked mint, and perilla, lime wedges, and sliced fresh chilli. Each diner assembles their garnishes to taste at the table.