Soak the vermicelli noodles in just boiled water for 2 minutes or until tender. Drain and divide among serving bowls. Or if you use rice instead, cook the rice as normally.

For the marinade, use a mortar and pestle to pound the spring onions and garlic to a rough paste. Stir through the remaining ingredients. Pour the marinade into a large bowl. Add the fish and toss to coat.

Heat the vegetable oil in a large non stick frying pan over medium high heat. Add the fish, spreading the pieces out in the pan. Allow to cook on first side until golden(about 2-3 mins) then gently turn the fish over, sprinkle over 2 tbsp of water. Cover with a lid and cook for 2-3 mins or until fish is just cooked. Scatter over most of the spring onions and dill (leave some for serving). Pour over lime juice and remove from heat.

Top noodles or rice with fish and the pan juices. Drizzle with nuoc Cham and add more dill or spring onion as needed.