1. Preheat the oven to 325ºF (160ºC.)
2. Spray a 9 to 10-inch (22-23cm) springform pan with nonstick spray. Dust the inside with cocoa powder, making sure to get it up the sides. Line the bottom with a round of parchment paper.
3. In a large bowl, mix together the cocoa powder, nuts, flour, candied citrus, cinnamon, ginger, black pepper, nutmeg, and red chile powder. Use your fingers to make sure all the ingredients are separate.
4. Melt the chocolate in a small bowl set over a pan of simmering water. Set aside.
5. In a pan fitted with a candy thermometer, heat the sugar and honey until the temperature reads 240ºF (115ºC.)
6. Pour the hot honey syrup over the nut mixture, add the melted chocolate, and stir well. Scrape the batter into the prepared pan and smooth the top. I start by using a spatula and as the mixture cools, once it’s cool enough to touch, I use a dampened hand to get it flat.
7. Bake the panforte for 30 – 35 minutes; the center will feel soft, like just-baked custard; if you touch it, your finger will come away clean when it’s done. (Do not overcook it, or it will be too firm once cooled.) Let the panforte cool on a wire rack for 15 minutes, then run a knife around the edge to loosen it from the pan. Remove the springform carefully (sticky edges might tear, so keep an eye out), then let cool completely.
Once cool, remove the bottom of the springform pan and peel away the parchment paper. Sprinkle the panforte with powdered sugar and rub it in with your hands.