Preparation FOR THE CAKE 1. Combine flour, cinnamon, baking powder and baking soda in a mixing bowl. 2. Blend in egg, mayonnaise and sugar, mixing well. 3. Stir in carrots, pineapple and walnuts. 4. Pour batter in a greased and lined 9" springform pan or muffin cups, filled 2/3 full. 5. Bake at 180°C - 200°C till toothpick test comes out clean. 6. Cool before unmolding.
TO MAKE THE FROSTING 1. Combine ingredients in a food processor. 2. Pulse till smooth. Spread over cake.