1Preheat oven to 350F (175C). Butter and flour 3 (8 inch) round cake pans.
2In a small mixing bowl whisk together cake flour, baking powder, baking soda, nutmeg, cinnamon, ginger and cloves.
3In a large mixing bowl, with an electric mixer mix the butter, sugar and salt until light and fluffy. Beat in the eggs, 1 at a time, beat well after each egg is added. Beat in the dry ingredients and the buttermilk alternately.
4When the batter is well mixed and smooth, divide it into the 3 cake pans and bake approximately 25 minutes or until a toothpick inserted in the center comes out clean. Let cool for 10 minutes.
5While waiting for the cakes to cool make the butter cream:
Beat the butter, shortening and salt together until creamy. Add half the confectioner's sugar and beat until fluffy (5 minutes). Combine vanilla extract and heavy cream. Gradually beat in the remaining confectioner's sugar alternating with the cream mixture until light and fluffy.
6If the cake layers have domed a little slice off the tops with a long serrated knife so they are flat and even.
7Place the first layer cut side down on whatever you're going to serve it on. Spoon about 3/4 cup of butter cream onto the center of the cake layer. Spread it to the edges. Repeat with the remaining layers. Garnish the top with nuts and cocoa powder