Preheat the oven to 150°C/300°F/Gas Mark 2, 10 minutes before baking. Lightly oil & line the base of a 15cm/6 inch deep square cake tin with greaseproof or baking paper
Sift the flour, spices, baking powder and bicarbonate of soda together into a large bowl
Lightly whisk the oil and eggs together, then gradually stir into the flour & sugar mixture. Stir well
Add the carrots and walnuts. Mix thoroughly, then pour into the prepared cake tin. Bake in the preheated oven for 1¼ hours, or until light & springy to the touch and a skewer inserted into the centre of the cake comes out clean.
Remove from the oven and allow to cool in the tin for 5 minutes before turning out on to a wire rack. Reserve until cold
For the frosting, beat the cream cheese, butter and vanilla essence together until smooth, then gradually beat in the icing sugar until icing is smooth. Add a little milk, if necessary. Spread the frosting over the top. Refrigerate for about 1 hour to set the frosting, then cut into squares and serve
Tasty tip: For a fruitier cake, add 1 grated apple and 50g/2oz of dried sultanas in step 5. To plump up the dried sultanas, soak for an hour or overnight in 300ml/½ pint of cold tea