½ cup unsweetened cocoa powder, plus more for dusting 1 teaspoon ground cinnamon ¼ teaspoon ground cayenne ¼ teaspoon kosher salt 8 ounces semisweet chocolate chips (1¼ cups) 10 tablespoons (1¼ sticks) unsalted butter, plus more for pan 6 large eggs, separated ½ cup packed dark brown sugar ½ cup granulated sugar Chocolate shavings and crème fraîche, for serving
