Preheat the oven to 180° C.

Whip the two types of sugar with the eggs for about 10 minutes or until it is light and fluffy.

Melt the butter and chocolate, let it cool a little and pour it into the egg mix.

Sift the flour, salt and baking powder and fold gently into the egg mix using a rubber spatula.

Chop the walnuts and milk chocolate and mix gently into the brownie dough. Pour the mix into a 25 x 30 cm baking tin, greased and lined with baking paper.

Bake the brownie for about 30 to 35 minutes at 180° C.

Remove from the baking tin and cool.

When cold, spread the thin layer of melted chocolate on top and use a fork to make a decorative texture.

Cut the brownie into 5 x 5 cm squares and enjoy.