Take a bowl add butter and chocolate heat on double boil method or microwave as shown in the video. After melting butter, chocolate add vanilla essence mix well. In another bowl break eggsadd sugar and beatwell to this mixture add butter chocolate, vanilla mixture and fold the mixture Now add flour, coco powder, walnuts and fold the mixture again. Take a baking tray grease it then pour the mixture evenly and bake at 350 degrees Fahrenheit for 30- 40mins