Gluten free carrot cake

I was given this recipe many years ago when my eldest was first diagnosed with coeliac disease.  It is a really lovely cake, and it always seems to work perfectly.  Noone believes me that it's gluten free when I serve it.  I happen to love carrot cake because of the frosting: cream cheese frosting is something wonderful.  I always make a double-batch of cream cheese frosting, because you need a really thick layer on a carrot cake, and because there has to be enough for me to lick the bowl!!

BEST GLUTEN FREE CARROT CAKE

Recipe can be made a day ahead.  Suitable to freeze.

 1 cup [125g] soy flour or chickpea [besan] flour

¾ cup [110g] maize cornflour [100% corn]
2 teaspoons gluten-free baking powder
1 teaspoon bicarbonate of soda
2 teaspoons mixed spice
1 cup [200g] firmly packed brown sugar
1½ cups [360g] grated carrot
1 cup [120g] chopped walnuts
½ cup [125ml] extra light olive oil
½ cup [125ml] sour cream
3 eggs, beaten lightly

ORANGE FROSTING:

125g cream cheese, chopped
1 teaspoon finely grated orange rind
1½ cups [240g] pure icing sugar

Preheat the oven to moderately slow [160 C].  Grease a deep 20cm round cake tin and line base and sides with baking paper. 

Sift flours, baking powder, soda, and spice into a large bowl; stir in the sugar, carrots and walnuts. 
Stir in the combined oil, cream and eggs until smooth.  Pour the mixture into prepared pan and bake in a moderately slow oven for about one hour.
Stand the cake for 10 minutes before turning onto a wire rack to cool.  Top cake with Orange Frosting.

Orange Frosting: Beat the cheese and rind in a small bowl with an electric mixer until light and fluffy.  Gradually beat in the sifted icing sugar until smooth.