Put the chestnuts into a small food processor and whiz until you get a fine breadcrumbs-like mixture.
Mix the flour and baking powder in a large bowl. Add the margarine/spread and rub it with your fingers until the mixture resembles breadcrumbs. Add the sugar, ground chestnuts, orange zest and cinnamon, then mix with a palette knife.
Slowly and gradually pour in the milk, mixing with the palette knife to make a dough.
Finally fold in the mincemeat and shape a ball. Rest in the fridge for an hour or so. ( The dough can be frozen too).
Heat the oven to 190°C.
Roll the dough out between two large baking sheets into 2cm thickness. Using a cookie cutter, stamp out circles. Put these onto a lined baking tray.
Bake for 10-15 minutes until they have risen and light brown.
Check their base if they’re cooked through. If they are ready, move them to a wire rack to cool.
Dust them with icing sugar just before serving.