Step 1

Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 12x18 inch sheet pan. In a saucepan, combine coffee, 1 cup butter and 5 tablespoons cocoa. Bring to a boil, reduce heat and stir until smooth. Remove from heat and set aside.

Step 2

In a large bowl, combine flour, white sugar, baking soda and salt. Make a well in the center and pour in eggs, sour cream and 1 teaspoon vanilla. Mix well, then beat in cocoa mixture. Spread into prepared pan.

Step 3

Bake in the preheated oven for 20 to 25 minutes, or until a toothpick inserted into the center of the cake comes out clean. Frost while still warm.

Step 4

To make the Frosting: In a saucepan, combine 1/2 cup butter, milk and 6 tablespoons cocoa. Bring to a boil, reduce temperature and stir until smooth. Remove from heat and blend in the confectioners' sugar. Stir in 1 teaspoon vanilla and chopped pecans. Spread on cake while still warm.