1- Pre-heat the oven to 180° (UK Gas Mark 4). 2- Break the chocolate into pieces and melt with 4 tblsp water.
3- Add 50 g butter and mix well to make it smooth, then leave to cool a little.
4- Put the walnuts into the mixer bowl and apply a few pulsed to reduce them into large pieces. Set aside.
5- Put the eggs, sugar and cinnamon into the mixer bowl. Mix for 30 seconds, gradually add the butter and then the flour, the baking powder and melted chocolate through the hole in the lid. Apply a few pulses to make the preparation smooth and even
5-Once the blender has stopped, add the crushed walnuts and mix with a spatula.
6- Pour the mix into a square cake tin lined with greaseproof paper. Bake for 20 minutes, then leave for 10 minutes before removing from the tin and allow to cool completely before cutting the cake into even sized squares
7- These brownies go wonderfully with custard.