Split the prawns down the middle and place them in a bowl.
Mix chopped chillies, grated ginger, and half the vegetable oil with the prawns.
Grill prawns cut-side down for two minutes on a hot griddle pan.
Turn prawns, add half the lime juice and zest, and cook for two more minutes.
Combine cooked noodles with pak choi, coriander, sesame oil, remaining lime juice, peanuts, and vegetable oil.
Add fine strips of ginger and chilli to the noodle mixture and season.
Mix sweet chilli sauce, passion fruit juice, and one teaspoon of lime juice for the sauce.
Arrange noodles and prawns on a platter with dipping sauce in the center.