In a hot wok, add the prawns and stir fry until prawns begin to change color. Add garlic, red shallots, pepper, shrimp paste, chile and spring onions and stir-fry for a further minute. Garnish with coriander (cilantro) and chile.
For the marinade: In a mixing bowl, combine the sugar, fish sauce, and chile powder and marinate the prawns for 20 minutes.