Louis Tikaram, the Fijian chef behind E.P. & L.P. restaurant in Los Angeles, shared this recipe for grilled sushi-grade tuna served over matchstick green mango in a spicy lemongrass dressing. Coconut husks (and charcoal made from those husks), the fuel of choice in Fiji, burn hot and clean, without imparting lots of smoky flavor into food. They are great for grilling fresh, meaty fish like tuna, which is quickly seared and only cooked to rare. You can find coconut charcoal (such as Kratos) at hardware stores or online, or substitute hardwood lump charcoal.