Place the flour, desiccated coconut, caster sugar and cold butter into a food processor. Pulse for 10–20 seconds, until the mixture resembles fine breadcrumbs.
Using the pulse function, add the cold water 1 Tbsp at a time, processing briefly after each addition, until the dough just comes together into a ball. Avoid adding too much water.
Wrap the pastry in cling film and chill in the fridge for 30 minutes or place in the freezer for 15 minutes.
Preheat the oven to 190°C and lightly grease a shallow muffin or tartlet tin.
Roll out the pastry on a lightly floured surface to about 3 mm thickness.
Cut out circles (about 8 cm in diameter) and gently press them into the holes of the tin.
Spoon 1–2 teaspoons of tropical mincemeat into each pastry case, being careful not to overfill.
Re-roll any pastry trimmings and cut out festive shapes (stars, hearts, etc.) to place on top. Lightly dampen the edges with water and press to seal.
Bake for 20–25 minutes, until the pastry is lightly golden.
Allow the mince pies to cool slightly in the tin, then transfer to a plate.
Dust with icing sugar before serving.