Line a 24-count mini muffin tin with cupcake liners. In a large bowl, mix together the macadamia nuts, papaya and pineapple.
Over a double boiler or in the microwave, melt the chocolate. Pour the melted chocolate over the nut and fruit mixture and stir to combine. The nuts and fruit should be completely coated in chocolate. Divide the mixture evenly among the cupcake liners, about 2 tablespoons in each. Sprinkle the toasted coconut or Hawaiian pink salt over the melted chocolate to garnish, if desired. Refrigerate to set for about 30 minutes.