Low Fat Carrot Cake

 250 g Flour, Wheat, White, Self Raising, (9oz)  2 teaspoons (as purchased) Baking Powder  1 teaspoons Bicarbonate of Soda  1/2 teaspoons Salt  110 g Sugar, Muscovado, light, (4oz) or soft brown sugar     2 medium Egg, Whole  1 teaspoons (level) Vanilla Extract     175 ml Milk, Skimmed, (6fl oz)  50 g Margarine, Soft, Polyunsaturated, (1 3/4oz), melted and cooled     225 g Carrots, Old, Raw, (8oz), finely grated  50 g Raisins, (1 3/4oz)To serve:  150 g Cheese, Soft, Medium Fat, (5 1/2oz)  2 teaspoons (level) Sugar, Icing     1 zest(s) of 1 Orange, 1 tsp finely grated orange rind    Preheat the oven to 350 F. Spray an 8" square baking pan with nonstick spray.Sift t6he flour, baking powder, cinnamon, baking soda and salt into a medium bowl.Combine the granulated sugar, egg, egg white and oil in a large bowl and stir until blended. Add the flour mixture and stir just until combined. Stir in the pineapple and reserved liquid, carrots and raisins. Scrape the batter into the pan. Bake until a toothpick inserted into the centre comes out clean, 25 to 30 minutes. Cool the cake in the pan on a rack for 10 minutes. Remove the cake from the pan and cool completely on the rack.Beat the cream cheese, confections' sugar and maple syrup in a medium bowl just until blended and smooth. Spread on top of the cooled cake. Cut into 12 squares.