Directions

1. Preheat the oven to 180°C. Grease a 22cm round tin and line with baking paper.
2. Whisk the oil and sugar together in a bowl, then add the eggs and whisk well to combine. Add the flour and fold in together. Stir in the grated carrot, orange zest and 1/2 cup of the walnuts. Spread into the prepared pan and bake for 40 minutes or until a skewer inserted in the centre comes out clean. Cool in the tin for about 10 minutes and then turn out onto a rack to cool completely.
3. For the icing, place all the ingredients in a bowl and beat together with electric beaters until smooth. Cut the cake in half horizontally with a large bread knife. Remove the top layer and spread half the icing onto the bottom layer. Replace the top layer and spread the rest of the icing on top, then sprinkle with the remaining chopped walnuts.