Preheat oven to 180'C. Mix all the cake ingredients together and pop into an 8 inch cake tin. Bake for approximately 90 minutes. Leave out on a wire rack to thoroughly cool before glazing. Combine wet icing ingredients to your required consistency. Drizzle over the cake diagonally (best done in an icing bag or sandwich bag with cut out corner!). Grate Lemon Zest on top of iced cake and sprinkle a little extra cinnamon on.