Preheat the oven to 350 degrees. Lightly grease a 13 by 9 inch pan.
2
Combine the flour, cocoa powder, and salt.
3
In a large bowl, beat the vegetable oil and sugar. Beat in the eggs one at a time. Beat in the vanilla extract. Gradually blend in the dry ingredients. Fold in the walnuts. Spread the mizture evenly in the prepared baking pan.
4
Bake for 25 to 30 minutes, or until a toothpick inserted in the center comes out clean. Coll in the pan on a wire rack before cutting into large or small bars.