In a large wide bowl, sift the flour and icing sugar. Rub in the butter with your fingers and crumble the flour and butter until it resembles crumbs.
Add to the bowl the egg, water, vanilla, ginger and cinnamon. Combine well until it forms a soft dough. Shape it into a slab and wrap it in plastic. Refrigerate for 2 hours.
Cover baking trays with baking paper to place the star cookies on. Pre heat oven to 170C fan forced.
Remove dough from fridge and separate into 4-5 sections. Knead each section gently until it becomes soft on a floured surface. Then between 2 pieces of baking paper, roll out to 5mm thick. Using a star cookie cutter, cut out the star and place onto baking tray. Repeat with remaining star cookie cutters and dough.
Bake for 15-17 minutes. Remove and allow to completely cool.
Decorate each star cookie with royal icing and assemble. Use the largest cookie as the base, start sandwiching the iced cookies together altering orientation.