For the topping: Preheat the oven to 350 degrees F and line a baking pan with parchment paper.
Toss the cashews and coconut with the oil, curry powder and salt in the baking pan. Bake, stirring once or twice, until the coconut is golden brown, about 5 minutes (be careful, it can burn quickly towards the end). Stir in the lime zest and cool completely. Transfer to a bowl and stir in the cilantro.
For the fish: Increase the oven temperature to 425 degrees F and line a baking pan with parchment paper.
Drizzle the parchment with olive oil and place the fish on top. Sprinkle all over with salt and pepper, turning the fillets to coat them with the oil. Sprinkle the top of the fish with the coriander and curry powder, then roast until the cod is just cooked through and flakes apart easily, 12 to 15 minutes.
Serve the fish with the cashew coconut topping and lime wedges on the side.