Adapted from a BBC Food recipe for our family.
For the shortcrust pastry
500g plain flour
1 tsp white wine vinegar
1 egg, beaten
For the filling
50g plain flour
350mlwhole milk, warmed
2 x 150g/chicken breasts, cut into chunks
125g good-quality ham, cut into strips
2 large leeks
5 tbsp chopped fresh tarragon
Rub the butter into the flour until it resembles breadcrumbs
Add the vinegar and enough cold water to make smooth dough.
Divide into two pieces, wrap in cling film and chill for 30 minutes.
Heat 25g of the butter in a frying pan and cook the chicken then add leeks and continue to cook until just soft.
Make a roux out of the remaining butter, flour and milk.
Stir in the chicken mixture, ham and tarragon.
Preheat the oven to 180C.
Roll a 25cm circle of pastry.
Put on a dish. Trim the edges.
Spoon in the chicken mixture and brush the edges of the pastry with the beaten egg.
Roll the second piece of pastry out thinly and cover the pie.
Seal and crimp the edges.
Cut a hole in the top of the pie and brush the top with the beaten egg.
Bake in the oven for 35-40 minutes.
Serve with mash.