Preheat oven to 350 degrees F. Grease a 9x1-1/2-inch round cake pan. Line bottom of pan with waxed paper; grease the paper. Set pan aside.
In a blender or food processor combine pecans, sugar, chopped chocolate, cocoa powder, baking powder, and baking soda. Cover; blend or process until nuts are ground. Add eggs and vanilla. Blend or process until nearly smooth. Pour batter into the prepared pan, spreading evenly.
Bake about 30 minutes or until a wooden toothpick inserted near center of cake comes out clean. Cool in pan on a wire rack for 10 minutes. Remove cake from pan; peel off waxed paper. Cool thoroughly on wire rack.
To serve, cut into 16 wedges. Place one wedge on each dessert plate and drizzle with Toasted Coconut-Pecan Caramel Sauce. Place another wedge on top at a different angle. Drizzle with more sauce.
Toasted Coconut-Pecan Caramel Sauce
Preheat oven to 350 degrees F. Spread coconut and pecans in a thin layer in a shallow baking pan. Bake for 6 to 8 minutes or until coconut is toasted and nuts are golden brown, stirring once or twice. Remove from oven. In a medium bowl stir together ice cream topping, coconut, and pecans. Serve immediately or heat slightly in microwave before serving.