Combine water, cocoa, and soda, stirring well. Set aside.
Cream shortening; gradually add sugar, beating well. Add eggs, one at a time, beating well after each addition.
Add flour to creamed mixture alternately with buttermilk, beginning and ending with flour. Stir in chocolate mixture, vanilla, and pecans.
Pour batter into a greased and waxed paper-lined 13- x 9- x 2- inch baking pan. Bake at 425° for 30 minutes or until a wooden pick inserted in center comes out clean. Cool cake completely. Pour Drippy Icing over top of cake. Cut cake into squares to serve.