Cream cheese frosting
1.Preheat oven to 180°C. Grease 8 holes of a 12-hole oval friand pan.
2.Beat oil, sugar and egg in a small bowl with electric mixer until thick and pale. Transfer mixture to a large bowl and stir in carrot, nuts and sifted dry ingredients. Spoon mixture into pan holes; bake about 20 minutes. Stand cakes in pan 5 minutes before turning, top-side up, onto wire rack to cool.
3.To make cream cheese frosting, beat butter and cream cheese in a small bowl with electric mixer until light and fluffy. Gradually beat in sifted icing sugar.
4.Spread cold cakes with cream cheese frosting. Serve topped with halved walnuts, if you like.