Add the eggs, brown sugar, and white sugar in a bowl and cream together for 3 to 4 minutes
Add vanilla essence to the egg mixture
Melt together 200g dark chocolate with 115g butter in the microwave, mix and set aside
Once the chocolate mixture has cooled, add it to the egg mix and mix gently
Sift in the all-purpose flour and cocoa powder and carefully fold it all in
Optionally add dark chocolate pieces to the batter
Transfer into a lined baking dish
Bake in a 180° preheated oven for about 40 minutes
Let it cool for at least 15 minutes before slicing
