Preheat oven to 180. In a large bowl mix the sugar, oil, milk, lemon juice, zest, vanilla seeds. Sift the flour, baking powder and bi-carb soda into a separate bowl. Add half of the flour mixture to the wet ingredients and mix. Add the rest of the flour, a cup of desiccated coconut and fold through until combined. Pour mixture into an oiled 20cm square baking dish. Sprinkle the rest of the desiccated coconut evenly on top of the batter. Bake for 30-35 minutes or until a toothpick inserted in the center comes out clean. In a small bowl sift the icing sugar and combine it with the lemon juice until you have a smooth icing. Allow the cake to cool completely before slicing. Drizzle the icing over the cake so it drips down over each piece. Garnish with lemon zest. .