Blend oil, sugar and vanilla in a mixing bowl. Add eggs; beat well with spoon. Combine flour, cocoa, baking powder and salt; gradually add to egg mixture until well blended. Stir in nuts. Spread in greased 9-inch square pan. Bake a 350*F for 20 to 25 minutes or until brownies begins to pull away from edges of pan. Cool in pan. Frost if desires; cut into squares. Makes about 16 brownies