1 c. butter, softened
2 c. sugar
2 eggs
1/4 c. (heaping) cocoa
2 tsp. vanilla extract
2 tsp. baking soda
1 c. sour cream
2 1/2 c. flour
1/4 tsp. salt

Cream butter and sugar in bowl until light and fluffy. Add eggs, one at a time, beating well after each addition. Add cocoa, vanilla and mixture of soda and sour cream. Sift in flour and salt. Add 1 cup boiling water; mix well. Grease and flour tube pan. Dust with additional cocoa. Pour batter into prepared pan. Bake at 325 degrees for 1 hour. Cool in pan for 15 minutes. Invert onto wire rack to cool completely.