Preheat oven to 350 F. Butter and flour a 9-inch round cake pan.
Melt the butter in a medium saucepan and remove from the heat. Stir in the cocoa, sugars, cayenne and salt until smooth and stir in the eggs. Sift the flour and Clabber Girl Baking Powder in the pan and combine well. Stir in the chocolate chips.
Spread the batter in the prepared pan and sift the powdered sugar on top. Bake in the middle of the oven for 45 to 50 minutes, or until a skewer comes out with crumbs clinging to it. Let the torte cool completely before frosting.
Topping: Place a 1/2 cup of dark chocolate and 2 teaspoons of shortening in a bowl and a 1/2 cup of white chocolate and remaining 2 teaspoons of shortening another. Heat in ten second bursts, removing every ten seconds to stir. Repeat as needed until chocolate is melted.
Pour melted dark chocolate on top of torte and, using an offset spatula, spread to an even finish. Drizzle white chocoalte top, then using a toothpick drag the white chocolate all through the dark chocolate in different directions for a marbled finish.
Cut into wedges.