Mix the ingredients for the spice mix in a small bowl.
Pat the fish dry with kitchen paper and rub it with the spice mix. Make sure to coat both sides. Cover and chill until you’re ready to cook.
Heat the grill (broiler) to high.
Prepare the pineapple by removing the core and cutting the flesh into spears.
Place the spears on a baking sheet and grill for about 6–8 minutes, or until they caramelize around the edges slightly. Set aside to cool completely.
Heat the oven to 220°C/200°C fan/425°F/Gas 7.
Place the fish on a baking tray lined with baking parchment and roast for about 12–15 minutes, or until it is cooked through.
While the fish is roasting, chop the grilled pineapple into small dice and mix them with the rest of the salsa ingredients, adding the lime juice in stages to taste.
Once the fish is cooked, serve it with the pan juices and the salsa on top.
