Chop 1 pound white chocolate into 1/2-inch pieces. Microwave all but 1 cup of the chocolate in intervals until melted, then add the rest of the chocolate; stir until melted. Pour onto a foil-lined baking sheet; spread until 1/4 inch thick. Sprinkle with 1/4 cup each chopped cashews, macadamia nuts, shredded coconut and chopped freeze-dried mango; press gently into the chocolate. Let harden completely, about 1 hour. Break into pieces.