Peel, core and finely dice the apples and place in a pan. Add all the remaining ingredients, except the brandy.
Heat over a low heat, stirring gently, until the butter has melted and the juices start to run. This will take around 10 minutes or so. Leave to cool.
Stir in the brandy when the mixture has cooled.
To prepare the pastry
Weigh the flour, butter and caster sugar into a food processor and blitz until it resembles breadcrumbs. Add a small amount of water and pulse again (just sufficient to combine the ingredients and form a mass of pastry).
Roll the pastry out onto a lightly floured pastry board. Cut circles with a pastry cutter to and place in a non-stick cup cake/fairy cake tray. Fill with the mincemeat taking care not to overfill as the mixture may spill out of the pies whilst cooking. Cover with a pastry lid. Beat the egg and use this to glaze the pastry.
To bake
Bake at 200oC, 400oF, gas mark 6 until lightly golden. This should take around 15 to 20 minutes. Turn the tray around part way through the cooking time so that they cook evenly.
Sieve icing sugar over the top of the mince pies when cooked. Leave to cool on a wire rack.