Spray an 8 or 9 inch square pan or brush with oil. Dust lightly with a little cocoa or flour and tap out excess.

In a medium pan, melt butter. Stir in cocoa and oil. Remove pan from heat and allow to cool for 15 minutes.

In a bowl, combine sugar and vanilla. Beat in eggs, one at a time, beating well after each addition.

Stir in flour and remaining ingredients (do not overmix to avoid tough brownies). Spread evenly in prepared pan.

Bake for 20 to 25 minutes or until center springs back when touched lightly with fingertip. Cool completely on wire rack before cutting into squares.