- STEP 1
Pour the stock into a medium size pan, add the lemongrass, garlic, ginger and two of the chillis and briskly boil for about 15 minutes to create the basic broth. Taste it and if neccessary add the other two chillis. Turn down the heat, cover the pan and leave to simmer for a further 15 minutes. This will allow the flavours to really develop.
- STEP 2
Add the prawns to the soup, and add three of the spring onions, the fish sauce and the herbs. Reserve a little of each herb for garnishing. Put the lid back on the pan, and leave it whilst you carry out step 3.
- STEP 3
In a pan of boiling water, cook the beansprouts for 1-2 minutes, or until they are just tender. Drain them and add them to the soup. Place the rice noodles in the boiling water and cook for 4-5 minutes (or less if using straight-to-wok noodles). Remove the lemongrass, ginger and garlic from the soup.
- STEP 4
Divide the cooked noodles between two deep bowls. Pour the soup over the noodles. Garnish with a little of the coriander and mint leaves, a few slices of red chilli and spring onion. Serve with a wedge of lime.