Finely chop the dark and white chocolate separately. In a medium bowl, microwave half of the dark chocolate at 50 percent power in 30-second intervals, stirring between intervals, until melted, about 2 minutes. Add the remaining dark chocolate and stir until completely melted. Repeat with the white chocolate in a separate bowl. Using a silicone or offset spatula, spread the dark chocolate evenly (about 1/4 inch thick) onto a parchment paper-lined baking sheet. Drop dollops of the white chocolate on top of the dark. Using the tip of a knife or skewer, swirl the white into the dark. Sprinkle with the pistachios, dried fruit, and coconut chips. Chill until set, about 30 minutes. Cut into irregular pieces.
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