Mix the flour, sugar and salt, then add the orange zest.
Dice the butter, then crumble it with the flour mixture until it resembles breadcrumbs (use your fingers or a blender).
Mix the egg yolks with the water - add this to the crumble and mix carefully until you get a dough, but don't overmix, otherwise it will be too sticky!
Form a big ball from the dough, wrap it in clingfilm and rest for 20-30 minutes in the refrigerator.
Preheat oven to 190°C. Grease a shallow muffin or tartlet tin.
Roll out the pastry on a lightly floured surface to 3 mm thickness. Cut out circles with a pastry cutter (or a mug), large enough to fill the base of the tin holes (about 8 cm diameter).
Gently press these disks into each hole and add 1 or 2 tsp of mincemeat. Don't overfill them!
Reroll the remaining pastry and cut slightly smaller disks to cover the mincemeat - or use a cookie cutter to stamp out star shapes and put these on top of the pies. Dampen the edges with water then press together.
If you'd like the pies to have a shiny glaze, lightly beat an egg, then brush the tops with it
Bake for about 20-25 minutes until lightly golden.
Let them cool in the tin a bit then transfer them to a plate. Dust with icing sugar before serving.