Wash the noodles and drain well. If using dried, pour (just under) boiling water over them for a few minutes before using.
Make the spice paste by blending the chillies, garlic and shallots in a food processor, until a paste is formed.
Heat oil in a wok or large frying pan, fry the paste for 2-3 minutes, continuously stirring.
Add the noodles and fry well for 5 minutes. Add the prawns, bean sprouts, cabbage, chives, light soy sauce and dark soy sauce. Mix well and fry for another 5 minutes or until the vegetables are cooked.
Make a well in the middle and add the beaten egg, stirring slowly until the egg is cooked. Add kecap manis and remove from heat. Serve steaming hot.