Preheat your oven to 180 deg c and grease and line a 20cm baking tin.
In a stand mixer combine the tahini and caster sugar and beat until light and fluffy (approx. 2-3 minutes).
Add the orange juice, zest and cognac and beat agin for 1 minute until well combined.
Add the flour, spices and baking powder and gently fold through ensuring it is all mixed well.
Pour into baking tin and cook for 45 mins. until a skewer inserted comes out clean. Allow to cool in the baking pan for 10 mins before removing and then allow the cake to cool completely before dusting with extra ground cinnamon and icing sugar.