Preheat oven to 350º

Combine oil, sugar, eggs, and vanilla. To this, add the flour, baking powder, and cocoa- mix well. Stir in chocolate chips and nuts as desired. Pour in a greased 9x13 pan. Bake for 30 minutes- or until a toothpick comes out clean.

For more fudgy brownies, take the brownies out of the oven about 5 minutes early. Chill completely before cutting.