Chocolate Cake with Cocoa Frosting

Directions

1. In a small saucepan over medium heat, combine cocoa and water until smooth; add the oil and butter. Bring to a boil; cook and stir for 1 minute. Remove from the heat.
2. In a large bowl, combine flour and sugar; gradually add cocoa mixture, beating until well combined. Beat in buttermilk and eggs.
3. Pour into a greased 15x10x1-in. baking pan. Bake at 350° for 28-30 minutes or until a toothpick inserted in the center comes out clean. Cool on a wire rack.
4. Cut cake into four 7-1/2x5-in. rectangles. Wrap two of the rectangles separately in foil; refrigerate or freeze. Set the other two rectangles aside.
5. For frosting, in a small saucepan, combine the butter, cocoa and milk. Bring to a boil; cook and stir for 1 minute (the mixture will appear curdled).
6. Pour into a large bowl. Gradually add confectioners' sugar and vanilla; beat until frosting achieves desired spreading consistency. Spread frosting between layers and over the top and sides of cake. Unfrosted cakes may be frozen for up to 6 months.