In a large saucepan over high heat, add rice, coconut milk, water and salt. Heat, stirring constantly, until boiling.
Reduce heat to a low, cover saucepan with a tight-fitting lid and gently simmer until all liquid has been absorbed. Remove pan from heat and set aside for 10 minutes. Fluff with a fork before serving.
Meanwhile, in a small bowl, combine spring onion, ginger, garlic, lime juice and honey.
In a heatproof jug, heat oil then stir into ginger mixture. Season to taste with salt and pepper and set aside to cool.
Preheat a grill to hot.
Lightly oil and season hapuka on the presentation side with salt and pepper. Place fish same-side down on the hot grill until seared with grill marks. Turn 90° and repeat the searing process, so grill marks run in the opposite direction.
Flip fish and continue cooking for another 3 minutes, being careful not to overcook it.
Divide coconut rice evenly between serving plates. Top with seared fish then pour over dressing and serve.