Prepare a baking sheet by lining it with parchment paper or a Silpat mat. Spread out most of the nut and fruit mix on the sheet (reserving some to decorate the top). Sprinkle with flaky finishing salt. Set aside.
Place chocolate in the top portion of a double-boiler. Melt slowly, stirring occasionally, until it is completely melted. Pour chocolate over the nuts and fruits in an even layer. Press extra nuts and fruits into the top. Sprinkle evenly with chile powder.
Put in the fridge for about one hour to cool. Break into smaller pieces and store in a sealed container in the fridge.