Denver Chocolate Sheet Cake

My all time favorite cake because it tastes amazing and is so easy ...

DENVER CHOCOLATE SHEET CAKE

2 1/3 c. flour 2 c. sugar 1 tsp. baking soda 1 c. butter 1 1/4 c. water 4 tbsp. cocoa 1/2 c. buttermilk 2 eggs, beaten 1 tsp. vanilla extract FROSTING: 1/2 c. butter 4 tbsp. cocoa 6 tbsp. buttermilk 1 tsp. vanilla extract 1 lb. powdered sugar 1/2 c. chopped walnuts or pecans FOR CAKE: Mix flour, sugar and soda in bowl. Bring butter, water and cocoa to a boil in saucepan. Pour over dry ingredients. Mix thoroughly. Add buttermilk, eggs and vanilla. Beat well. Pour into greased 9"x13" pan and bake at 350 degrees for 30 minutes or until done. FOR FROSTING: To make frosting, heat butter, cocoa and buttermilk to boiling. Remove from heat and mix in vanilla, sugar and nuts. NOTE: A delicious, moist chocolate cake. The frosting will be runny but hardens as it cools. Cake freezes well