Khao piak sen with mushroom broth

Step 1: Char 1 onion and 1 oz fresh ginger cut side down in a dry pan over a high heat for 4–5 minutes, until blackened in patches.

Step 2: Put them in a large pot with 8 dried shiitake mushrooms, 1 stalk lemongrass and 2 litres water. Bring to the boil, then simmer over a medium-low heat, partly covered, for 30 minutes, until the broth is deep brown and smells savoury.

Step 3: While it simmers, make the noodles. Mix 7 oz rice flour, 3 ½ oz tapioca starch and ½ tsp salt in a bowl, pour in 1 cup boiling water and stir with chopsticks, then knead for 4–5 minutes once cool enough to touch, until you have a smooth, soft dough like play dough. Add a spoon more water if it cracks, a spoon more tapioca if it sticks.

Step 4: Dust the worktop with tapioca and roll the dough out 3 mm thick. Fold it loosely in three, cut into 4–5 mm wide strips with a sharp knife, and toss them immediately in more tapioca to keep them separate.

Step 5: Put 8 cloves garlic and 4 tbsp vegetable oil in a cold small pan over a medium-low heat and stir for 4–5 minutes, until the garlic turns pale gold and smells nutty. Pour into a heatproof bowl; it keeps darkening off the heat.

Step 6: Strain the broth, discarding the onion, ginger and lemongrass. Slice the shiitake caps and put them back in, with 7 oz oyster or king oyster mushrooms, 2 tbsp tamari, 1 tsp salt and 1 tsp sugar.

Step 7: Bring the broth to a rolling boil, shake the excess starch off the noodles and drop them in, stirring at once. Cook for 4–5 minutes, until they float, turn translucent and feel soft and chewy, and the broth has thickened. Common mistake: cooking the noodles separately in water; the whole point is that their starch thickens the soup.

Step 8: Ladle into bowls and top each with a spoon of fried garlic and its oil, 3 spring onions and 1 handful coriander leaves. Serve with 1 lime and 1 tbsp chilli oil or sliced chilli.