Whisk together melted butter, oil, eggs, water, and sugar until creamy
Add baking powder, salt, powdered sugar, cocoa powder, flour, chocolate chips, and vanilla
Mix well together
Pour into a baking pan (use double batch for extra thickness)
Bake at 325°F for about 60 minutes or until the center is no longer risen and is flat and level
Cool on the counter for 15-30 minutes before serving
