Buttermilk Cocoa Cake recipe.

Ingredients
1/4 cup baking cocoa
1 cup water
1/2 cup butter, cubed
2 cups all-purpose flour
2 cups sugar
1 teaspoon baking soda
2 eggs, lightly beaten
1/2 cup vegetable oil
1/2 cup buttermilk
BUTTERMILK FROSTING:
1/4 cup baking cocoa
1/2 cup butter, cubed
1/2 cup buttermilk
3 3/4 cups confectioners' sugar
1 teaspoon vanilla extract
1/2 cup chopped pecans

Directions
In a large saucepan, combine the cocoa and water until smooth; add butter. Bring just to a boil. Remove from the heat. In a large mixing bowl, combine the flour, sugar and baking soda; add cocoa mixture. Combine eggs, oil and buttermilk; add to cocoa mixture and beat until smooth. Pour into a greased 13-in. x 9-in. x 2-in. baking dish. Bake at 350 degrees F for 30-35 minutes or until a toothpick inserted near the center comes out clean.
In a large saucepan, bring the cocoa, butter and buttermilk to a boil. Remove from the heat. Whisk in confectioners' sugar and vanilla. Spread over the warm cake. Sprinkle with pecans if desired. Cool on a wire rack.