In a medium bowl, combine grated carrots,sherry and brown sugar. Set aside for 60 minutes.
Preheat oven to 350 degrees F (175 degrees C). Grease a medium size bundt tin .In a large bowl, beat eggs until light. Gradually beat in the white sugar, oil and vanilla. the. Combine the flour, baking soda, salt and cinnamon, stir into the wet mixture until absorbed. Finally stir in the carrot mixture and the walnuts. Pour evenly into the prepared pan.
Bake for 45 to 50 minutes in the preheated oven, until cake tests done with a toothpick. Cool for 10 minutes before removing from pan. When completely cooled, frost with the cream cheese frosting.
Heat 3 tbsp of sugar in pan until it melts and turns into toffee. Add walnuts and coat. Turn out onto baking paper and refrigerate until the toffee sets. Beat cream cheese and icing sugar until well combined.Mix in the vanilla essence and the ginger powder.
Spread the icing all over the cake and top with the toffeed walnuts.