Combine all the ingredients, except for
the carrots and walnuts, in a large mixing bowl. Stir with a wooden spoon until the
mixture is smooth, or beat on low speed in a food processing machine. Stir in the carrot and walnuts. Pour the mixture into a 20 cm (8") ring
tin which has been well greased. Bake in a preheated moderate oven
160C/325F/Gas 3 for 45 minutes. When cooked, leave the cake to stand
for 5 minutes before turning out to cool on a wire rack. Beat the softened butter and cream
cheese together until the mixture is smooth and creamy. Add the lemon rind and sifted icing
sugar and continue beating until the icing is quite smooth. Ice the cake with a spatula.
Carrots are rich in vitamin A, B and C and, because of
their very pleasant flavor, they are used frequently in sweet and
savory dishes, especially in cakes where they add moistness and a
lightness to the texture. Use young, fresh carrots whatever possible.
