Heat vegetable oil in a wok over low heat,add laksa paste and stir for about two minutes until aromatic.
Add stock and bring to the boil then reduce heat and simmer for two to three minutes.
Add prawns and snake beans and simmer until prawns just change colour. Add coconut milk and stir for one to two minutes.
Place noodles in a large bowl and cover with boiling water,stir with chopsticks to separate,then drain.
Divide noodles between four deep bowls and spoon laksa over noodles. Top with bean sprouts,coriander and mint. Serve with a wedge of lime.