For a lovely golden shine to your pastry you need to glaze it with an egg wash before baking.
Use egg yolks for a deep mahogany glaze, or thin down egg yolks with a little milk for a lighter gold. For sweet pies and tarts, mix the yolks with a little icing sugar.
To build up a thick glaze, brush a thin layer of your egg wash over the pastry using a pastry brush, then let it dry in the fridge for 10-15 minutes before applying a second coat. Alan does this 3 times to build up a thick and golden varnish.