Bring 3 litres of water to boil in a large pan.
In another pan, heat a little oil and fry the prawn heads until dry and fragrant.
Add some boiling water to the prawn heads and press them using a potato masher. This will help to release more flavour into the soup.
Pour the prawn heads and the juices into the large pan of boiling water.
Lower the heat to medium-low, cover with a lid and simmer for 1 hour.
Using the Kenwood Food Processor FDM302SS's miller attachment, blend the soaked dried shrimp until finely chopped. Add the water that was used to soak the dried shrimp into the prawn stock.
Switch out the miller and attach the blender. Add in all the rempah ingredients and blend into a paste.
Gradually add more water to facilitate the blending.
Heat oil in a frying pan. Fry the rempah paste till it turns dark red on medium-low heat. This step can take 15 - 30 mins.
Once the colour has changed, add in the chopped dried shrimp and fry till evenly mixed with the paste.
Remove the prawn heads from the stock and add the cooked rempah paste into the pot.
Bring the stock back to a boil, then add coconut milk while stirring.
Turn the heat down to medium or medium-low. Add beancurd puff and bring the stock to a soft boil.
Once the stock has come to a soft boil, add a little salt and sugar as desired.
Cook the noodles in boiling water before placing them in a serving bowl.
Pour on the laksa gravy, add your favourite toppings, and serve hot.