Measure the flour, Xantham gum, salt, almonds and icing sugar into a medium sized mixing bowl
Cube the butter and add to the bowl then rub in with your fingertips. Reach to the bottom of the bowl to ensure all flour is incorporated and shake the bowl a few times so any large chunks of butter float to the top. Keep mixing until just combined and the mix starts to clump
Add the egg yolk and mix with a blunt knife. Tip the dough out and knead briefly. It will be sticky (see notes), so use a scraper to remove it from the work surface if necessary
When smooth shape into a ball and flatten to a disc approx 2 cm thick. Wrap in clingfilm and chill for 2 hours until very firm
Roll out to a thickness of 2mm on a floured work surface. It will be stiff for the first couple of rolls but soon softens. Keep your rolling pin lightly floured and turn the pastry a ¼ turn frequently to prevent it from sticking to the work surface
Cut out 12 circles to line your pie tins and press gently into the cavities
Fill each pastry shell with 1 ½ tsp mincemeat
Cut out 12 circles, stars or a mix and use to top the pies, using a little beaten egg to moisten the edges of the circles and tips of the stars. Press the tops gently onto the pastry case to seal the pastry tops and bases together
Cover with clingfilm and chill for 30 minutes. Meanwhile preheat the oven 175C/ 350F/ GM 4
Just before baking cut a slit into the fully covered pies to allow air to escape and brush the pastry tops with beaten egg
Bake for approx 20-23 minutes until crisp and golden. Allow to cool for 5 minutes in the tin, then transfer to a wire rack to cool completely
Dredge with sieved icing sugar before serving