If you can’t find already ground almonds or hazelnuts, you can grind your own using a coffee grinder or high-powered blender. The cake can be served with whipped cream or coffee ice cream, but frankly, it’s perfect as is. Serves 8 7 ounces high-quality dark chocolate (at least 70 percent cacao), roughly chopped 6 large eggs, separated 1 cup powdered sugar, plus more for dusting 1/3 cup almond flour 1/3 cup hazelnut flour Butter or oil for greasing the pan Preheat the oven to 325 degrees F. Generously grease a 9-inch round cake pan. Melt the chocolate over a double boiler until smooth. Set aside. In a large bowl, using an electric handheld mixer or by hand, whisk the egg yolks and sugar until pale in color and doubled in volume. Clean the whisk well, making sure that no grease remains, and in a separate bowl, whisk the egg whites …