1) In a mixing bowl whisk together butter, sugar and one egg.
2) Melt half of the chocolate and add it to the egg batter.
3) Add the refined flour and cocoa powder sifted together to the batter.
4) Add a pinch of salt to the batter.
5) Add the remaining of the chocolate broken into small pieces.
6) Spread the batter in a baking tray.
7) Spoon out the peanut butter on top of the batter and give it a swirl.
8) Bake the brownies at 180 degrees for 30 mins.
9) Dust with the icing sugar or cocoa powder and serve.