One Bowl Method:In a large bowl, mix melted butter (make sure it has been cooled) and sugars. Add oil and vanilla. Mix well. Add eggs one at a time, mixing each time. Add flour and cocoa. Mix well.Pour in 8 x 8 baking pan (lined with parchment paper). Bake in preheated 350 F oven for 25 minutes.Cool and cut into squares. Enjoy!!!