Put the lemongrass, garlic, ginger, turmeric, curry powder and chillies/chilli flakes in a blender along with a splash of water and blend to make a coarse paste.

Heat the oil in a large saucepan over a medium heat, add the paste and cook for about 2 minutes until fragrant and beginning to stick. Stir in the peanut butter and cook for 1 minute until thickened.

Add the fish sauce, sugar, coconut milk and 1 litre (35fl oz) water, then add the lime leaves. Bring to the boil, then reduce to a gentle simmer.

Add the tofu and cook for about 10 minutes until the flavours have come together. Taste and adjust the seasoning, adding more fish sauce, sugar and lime juice to taste.

Meanwhile, cook the noodles according to the packet instructions in a separate pan, then drain and divide among four serving bowls.

Ladle the hot broth over the noodles, making sure each bowl gets some tofu. Scatter with herbs and top with crispy onions (or roasted peanuts). Serve with lime wedges on the side.

A note on preparing lemongrass: Trim the root and any tough top of the stalk. Peel away the outer woodier, fibrous, drier layers of the lemongrass until you get to the pale yellow, tender core. You can then either smash the lemongrass with something heavy, like a rolling pin, for example, to bruise the stalk and then use the stalk to infuse liquids as they cook (don’t eat it), or you can finely slice or mince the pale inner stalk and use as you would ginger or garlic. Any discarded bits of lemongrass can also be used to infuse liquids, but you will need to discard these pieces to serve.