Step 1

Make up the vegetable stock using boiling water and a stock cube if you don’t have fresh stock. Peel and finely chop or grate the garlic, ginger and chilli. Fry them all in a shot of vegetable oil in the bottom of a large pan for 1 minute or so to release their flavours and aromas.

Step 2

Pour in the warmed vegetable stock and bring to a gentle simmer. Bruise the lemon grass with the back of a knife and add to the soup with the lime leaves.

Step 3

Slice the mushrooms thinly and add these to the simmering stock. Dump the noodles, fish sauce and juice of the lime, stir well and simmer for about 3 minutes.

Step 4

Add the prawns and stir through with the pak choi, coriander and spring onions, simmering for just a minute or so more.

Step 5

Splash in a glug of coconut milk as you serve if you like (optional). Serves 2