Carrot and walnut cake with coconut icing (dairy free)

I was asked the other day if I had a good recipe for carrot and coconut cake. My friend loved carrot cake, but was currently on a dairy free diet, and the only ones he had eaten so far hadn’t been up to much. Either they been so heavy you could build a house with, or the were delicious on the day but then tasted dry and desiccated the day after. Could I help?
Carrot cake is usually made with oil rather than butter and this gives the cake a deliciously moist and springy texture which usually keeps well for several days. Traditionally it is served with a luscious cream cheese icing which goes perfectly with the carrot cake. However since dairy was out of the equation what else could I use? A couple of years back whilst travelling through Cambodia, I came across the most amazing fresh coconut cake. Deliciously light, yet still soft and moist inside. It was made from carrots, mashed banana and mixed with a sublet blend of spices then covered in a wonderfully rich coconut icing and topped with freshly sliced coconut. This recipe is my version of that fabulous cake.

Carrot and walnut cake with coconut icing 
difficulty: easy                                     Serves:8-10
110g grated carrot
2 large eggs
2 medium ripe bananas mashed
zest and juice of an orange
100ml sunflower oil
50 ml hazelnut oil
250g self raising flour
150g soft brown sugar
1/2tsp ginger
1/2tsp nutmeg
1/2tsp ground cinnamon
2tsp baking powder
70g chopped walnuts
1 fresh coconut
Coconut icing
400g tinned coconut cream chilled in the fridge
150-200g icing sugar
1tsp good vanilla essence or paste
Line a 2ocm loose bottomed cake tin with baking parchment and preheat the oven to 180C gas 4 (or 170C for fan ovens).

Place the mashed banana in a bowl with the orange zest and juice, walnuts and grated carrots. Beat the eggs together in a jug and add the sunflower and hazelnut oil and mix well. Add this to the carrot and banana mixture and stir together. Stir in the sugar then sieve the flour,spices and baking powder into the mixture and mix together. spoon the mixture into the prepared tin and bake in the middle of the oven for 45-55 minutes. (A skewer should come out clean when cooked). Leave to cool on a wire rack.
Whilst the cake is cooking, now make the coconut icing. Without shaking the tin, carefully open the coconut cream and scrape out the coconut cream leaving the liquid behind (this is great added to smoothies). Place this in a bowl and sieve in the icing sugar. Add the vanilla essence and mix till smooth. (you may need to add more icing sugar if the mixture is too wet). When the cake is cool, remove from the tin, slice in half and spread a third of the icing over one half. Place the over half on top and cover with the remaining icing.
Now comes the fun part, using a sharp metal skewer (I find a phillips screwdriver also works well for this ), pierce a whole in one of the 3 dimples at the top of the coconut and drain off the coconut water. (Again save this for smoothies). Take a hammer or wooden rolling pin, and bash the coconut till it opens. Once open, remove the hard outer shell leaving the thin brown skin on the white coconut flesh. Using a mandolin or truffle grater if you have one, slice the coconut into very thin slices. Arrange the coconut slices in a circular pattern over the cake.