Carrot cake with cream cheese frosting

Ingredients

• 1 cup brown sugar
• 1 cup vegetable oil
• 3 eggs
• 2 cup self raising flour
• 1 teaspoon ground cinnamon
• 1 teaspoon ground nutmeg
• 1/2 teaspoon bicarbonate of soda
• 2 cup carrot, grated
• 1/2 cup walnuts, finely chopped, plus extra to serve
• Frosting
• 250 gram softened cream cheese
• 50 gram softened butter
• 2 cup sifted icing sugar