For the cake: Preheat oven to 400 degrees and grease a 13 by 9 inch baking pan. In a medium bowl stir together flour, baking soda, cinnamon, and salt, set aside.

In a large mixing bowl with an electric mixer on medium speed beat together butter, oil, sugar, eggs, milk, water, and vanilla. On low speed gradually add flour mixture and beat until blended.

Pour into prepared pan and spread evenly. Bake until toothpick inserted into the center comes out clean, about 20 to 25 minutes. Make the icing while the cake is baking.

For the icing: In a medium saucepan stir together milk and cocoa. Add butter, heat until butter is melted, stirring constantly over medium heat.

Gradually stir in powdered sugar and vanilla. When the cake is just out of the oven spread icing over and sprinkle with pecans. Let cake cool completley on a cooling rack.