Mix together the oyster sauce, chili powder, sesame oil, ketchup and water.
In a large pot of water, boil the fishballs, fishcakes, prawns. Boil until the fishballs have floated to the surface and the prawns are pink. Blanch the beansprouts until cooked but still crunchy. Remove from pot.
Put meepok into the water and blanch for about 3-5 minutes. Remove and rinse with cold water.
Separate the sauce mixture, ingredients and meepok into 6 portions. Add lettuce, shallots and spring onions. Serve in bowls. Mix well before eating.