Directions

1. HEAT oven to 400°F. Spray 13 x 9-inch pan with no-stick cooking spray. Combine buttermilk and baking soda in small bowl; mix well.
2. COMBINE 1/4 cup cocoa, water, 1/2 cup butter and oil in medium saucepan. Bring to a boil over medium heat, stirring constantly.
3. REMOVE from heat; stir in buttermilk mixture and 1 teaspoon vanilla. Add eggs; blend well. Add flour, sugar and cinnamon; mix well. Pour batter into prepared pan.
4. BAKE 15 to 20 minutes or until toothpick inserted in center comes out clean. Cool 1 hour or until completely cooled.
5. COMBINE 1/4 cup cocoa, 1/2 cup butter and milk in medium saucepan. Bring to a boil over medium heat, stirring constantly. Remove pan from heat. Stir in vanilla. Gradually stir in powdered sugar; blend until smooth. Spread frosting over top of cooled cake.