Special utensils: Greased and floured 9 x 12 x 2 inch cake pan.
Preheat oven to 350F. In a saucepan, mix butter, cocoa and water well until bubbly. Remove from heat. Add buttermilk and eggs. Add sugar, flour, baking soda and vanilla. Mix well. Pour into prepared cake pan. Remove from oven while still warm. Spread with peanut butter.
Heat butter, cocoa and buttermilk until bubbly. Remove from heat. Add powdered sugar and vanilla. Mix well; spread on cake. Cut when cooled.
Cajun Country -- New Iberia, Louisiana