Preheat the oven top 180˚C and cover a square 20 x 20 cm tin with baking paper.
Combine the sugar and the eggs and mix on high speed until fluffy and doubled in size. Approximately 3-5 minutes.
Stir through the almond flour, coconut flour, cacao, orange juice and zest and vanilla and combine well.
In the mean time melt the chocolate together with the ghee. I usually do this au bain marie
As soon as the ghee and chocolate are melted together and are smooth, take of the heat and allow to cool before you stir it into the brownie mixture.
Add the chopped walnuts as the last step.
Add the batter into the baking tin and bake in the preheated oven for about 30 minutes or until a wooden stick comes out clean. It doesn't have to be entirely dry but also not too wet.