Either rub the butter gently into flour with fingertips until the mixture looks like breadcrumbs or (my preference) put in a food processor and pulse the butter and flour together
Add the orange zest, egg yolk and water (add bit by bit - you may not need it all) and mix with a knife or process for a few seconds until you have a smooth pastry dough
Wrap in greaseproof paper and chill in the fridge for 30 minutes
Preheat the oven to 180°C
If you have only one mini muffin pan, cut the pastry in two, return one portion to the fridge and make the pies in batches
Roll out the pastry thinly (thinner than you think you need – to avoid pastry-heavy pies), and use a small cookie cutter for the base to the mince pie, and a star shape, or smaller circle for the top. Push the bases into the tin, fill with a dollop of Eat Drink Live Well's homemade mincemeat, and put the top on
Use a pastry brush to brush the top of the pies with beaten egg
Bake in the oven for 15 minutes, keeping an eye on them so they don’t burn.
Leave in the tin for 5 minutes before cooling on a wire tray.