Preheat the oven to 180°C } 350ºF, and butter and line a 23cm / 9 inch springform cake tin.
Add maple syrup, cacao and butter to a saucepan over low heat. Stir with a wooden spoon until butter has melted and a paste has formed. Stir in the coconut sugar and then the Guinness and stir until the sugar is dissolves and the mixture is starting to bubble slightly. Remove from heat and allow it to cool slightly.
Whisk eggs, coconut milk and vanilla together in a bowl and then whisk into to chocolate mix, making sure you keep beating until all mixed in and smooth so that the eggs don't set. Then whisk in the almond meal, coconut flour and baking powder.
Pour into prepared pan and bake 45 mins or until a skewer comes out clean. Allow to cool in pan 15 minutes before removing and cooling completely on a wire rack.
To make the ganache, add all ingredients to a saucepan and stir until smooth and combined. Allow to cool slightly before spreading over the cake.