Our very own food director, and former food editor to Delia Smith, Sarah has written more than 1000 recipes for the magazine. She is also author of the delightful baking book, Family Baking and Marmalade; A Bittersweet Cookbook.
1Preheat the oven to 180°C, fan 160°C, gas 4. Sift the flour, baking powder and spices into a bowl. Add the eggs, sugar and oil; whisk.
2In another bowl, mix the carrots, pistachios, sultanas and lime zest. Fold into the egg mixture. Divide the mixture between three greased and lined 20cm x 4cm sandwich tins. Level with the back of a spoon, then bake on the middle shelf for 25 minutes.
3For the frosting, whisk the butter for a minute. Add the other ingredients; combine.
4Cool the cakes, then turn out on to a wire rack. Layer the cakes with the frosting, then coat the outside. Dust with cinnamon and top with blueberries and lime zest.
It's important to use real Philadelphia cream cheese for the icing, as it contains natural stabilisers that help give a thick and fluffy icing. Don't be tempted to use low-fat versions or 'soft white cheese' instead