1. Combine the mangos, pineapple, onion, chiles and lime juice in a spacious bowl.
   
   
2. Cover with plastic wrap and refrigerate for 4–6 hours or overnight.
   
   
3. About an hour before serving time, remove the salsa from the refrigerator and bring to room temperature.
   
   
4. Preheat the barbecue grill to medium.
   
   
5. Rub the fish with the olive oil and sprinkle it with salt and pepper.
   
   
6. Add the cilantro to the salsa and season to taste with salt; set aside.
   
   
7. Grill the halibut approximately 3 ½ minutes per side. The fish should be white throughout and just starting to flake.
   
   
8. Plate the halibut and top with the mango-pineapple salsa.

Note: Precise cooking time will vary depending on the proportions of your cut of fish. Ask your fishmonger’s advice about how many minutes per side. When grilling fish, it’s better to err on the side of under-cooking. When you remove the fish from the grill, immediately tent it with foil for a few minutes. The residual heat will finish off the cooking without drying the fish.