Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 9x13 inch pan. Sift together the flour, sugar, baking soda, baking powder, cocoa and salt. Set aside.
Melt the shortening in the boiling water, then stir into the flour mixture until blended. Beat in the eggs, then stir in the vanilla.
Pour batter into prepared pan. Bake in the preheated oven for 30 minutes, or until a toothpick inserted into the center of the cake comes out clean. Allow to cool.
