Beat butter and sugars in an electric mixer until pale and fluffy (5-6 minutes), scrape down sides of bowl, add egg and beat to combine. Add flour and spices, beat to just combine (1-2 minutes), then add fruit mixture and beat to just combine. Turn onto a lightly floured surface, halve and knead each half into a smooth disc. Roll out each disc on a piece of lightly floured baking paper to 5mm thick and refrigerate until firm (1 hour).
Preheat oven to 180C. Cut out stars with a well-floured 5cm star cutter, pressing firmly to cut through fruit (re-roll scraps and rest for 30 minutes before re-cutting). Place on oven trays lined with baking paper and bake, swapping trays halfway through, until golden on edges (12-15 minutes). Cool on trays for 5 minutes.
Meanwhile, for cinnamon-brandy glaze, stir sugar, cinnamon, brandy and 30ml water in a bowl until smooth. Dip biscuit tops into glaze, shake off excess glaze, place on a wire rack over a tray to set (30 minutes) then serve. Stars will keep in an airtight container for a week.