700 g fresh prawns, peeled and deveined (keep shells for stock)
1.5 L water
1 red onion, sliced
1 stick lemongrass, bashed and chopped
6 kaffir lime leaves, ripped
80 g ginger, peeled and grated
5 cloves garlic, crushed
2 limes, juiced
2-3 Tbs fish sauce
200-400 ml coconut milk
1/2 bunch coriander, ripped
2 Tbs red chillies, sliced
2 sticks shallots, chopped
200 g mushrooms, small buttons, left whole
1 lime, cut into wedges for garnish
Place the prawn shells in a pot with a little oil, cook until they turn pink/red. Bash the prawns with a wooden spoon to release the flavour, add the lemongrass and cook for a further 5 minutes to soften.
Add the water and bring to the boil, simmer for 10 minutes.
Once cooked, strain the stock through a strainer, retaining the stock and discarding the shells.
In another pan, cook the onion, garlic and ginger until the onion becomes soft and translucent. Pour in the stock, add lime leaves, lime juice and fish sauce. Allow to simmer for 5 minutes, add mushrooms and leave for a further 5 minutes.
Add the coconut milk, depending on how creamy you like the soup. Check the flavour, adding more lime juice or fish sauce as required.
Turn up the heat to a rolling boil, add the prawns, a few chillies and some shallots. After about 3 minutes when the prawns are cooked, scoop out the soup and place into serving bowls. Top the soup with more chopped shallots, coriander, red chillies and a few lime wedges.