Dissolve cocoa powder in boiling water, then allow to cool. Cream butter and sugar until light and fluffy. Add eggs one at a time, beating well after each addition. Add vanilla. In a medium bowl, combine flour, soda, powder and salt. Alternately add buttermilk, cocoa mixture, and dry ingredients to creamed mixture, beating well after each addition.

Pour into three greased and floured 9" round cake pan. Bake at 350 for 20-25 minutes or until tests done with a toothpick. Cool slightly before removing from pans, then remove and allow to cool completely on a wire rack.

Line an 8"round cake pan with foil, then grease the foil with butter. Sprinkle with pecans and set aside. In a large saucepan, combine sugars, 1/2 cup cream, corn syrup, and butter. Bring to a boil over medium heat, stirring until smooth and blended, about 5 minutes. Gradually add remaining cream. Bring to a boil over medium-low, stirring constantly. Cook and stir until the mixture reaches 238 degrees (soft-ball stage) then remove from heat. Quickly pour into prepared pan (do not scrape saucepan). Cool.

Line an 8"round cake pan with foil, then grease the foil with butter. Sprinkle with pecans and set aside. Place chocolate chips in a small bowl. In a small saucepan, bring cream just to a boil. Pour over chocolate and whisk until smooth. Pour over pecans. Cool to room temperature, then chill until set.

Melt unsweetened chocolate and chocolate chips in a microwave, stirring at intervals until smooth. Cool slightly. Beat the powdered sugar sugar, butter, milk, cocoa and vanilla until smooth, then beat in melted chocolate.

Level cakes and set aside. Spread dab of icing onto the serving plate, doily, or cardboard to hold the cake in place, then put one layer of cake down. Remove the foil from the caramel and place on top of the cake. Top with another cake layer. Remove the foil from the ganache and place on top of the cake. Top with the remaining cake layer. Frost top and sides of cake. Garnish and decorate as desired.