Preheat the oven to 180 degrees Celsius.
In a large mixing bowl add almond meal, coconut flour, carrot, walnuts, baking powder, cinnamon and nutmeg. Mix to combine.
In a separate smaller bowl add eggs, coconut oil and maple syrup. Whisk thoroughly to combine.
Pour egg mixture into dry mixture and stir through with a wooden spoon to combine.
Pour the cake mixture into a baking paper lined 18cm cake tin. Smooth the surface out with a spoon and place in the oven.
Bake for one hour and ten minutes or until golden brown on top and the skewer comes out clean.
To make cream cheese, blend all of the ingredients until smooth and creamy. Once cake is completely cooled, frost cake and top with walnuts and lemon zest.