1. Preheat the oven to 350 degrees. Butter two 9-inch cake pans and then dust with flour, knocking out any excess. In a medium bowl sift the flour, cocao, baking soda and salt. (There will be about 2 tablespoons of bran left in the sifter, discard.) In a small bowl mix together buttermilk, sour cream and herbal coffee, set aside. In bowl of mixer with paddle attachment cream the butter, whole cane sugar and muscovado. Start on low speed and then increase to high. Beat for about 5 minutes, until light. Add the eggs and vanilla and mix on low speed until just incorporated. Scrape down bowl. With mixer on low speed add a 1/3 of the buttermilk mixture followed by 1/3 of the flour mixture. Repeat twice ending with the flour mixture. Mix until just incorporated.
2. Pour batter into prepared pans and bake for 25 minutes, or until a cake tester comes out clean. Cool on a cooling rack, for about 10 minutes, and then remove from pans and cool completely.

To assemble:

1. Place one cake layer on cake stand and top with about 3/4 cup of icing. Place second layer on top and front the top and sides.