USING LEFTOVER ROAST BEEF RECIPES

1. Heat the butter in a large frying pan over a medium high heat. Add the leek chunks and cook them until they start to soften and brown around the edges.

2. Add the mushrooms and bacon to the pan, and continue to cook until the bacon has cooked through and the mushrooms have softened and started to brown. While they are cooking, toss the chicken in the flour with a generous amount of salt and pepper.

3. Add the chicken and flour mixture to the pan, and stir in until the flour has formed a very thick paste. Depending on how much chicken you're using, the pan may be getting a bit full at this point, but don't worry! It won't affect the flavour and nothing will over- or undercook.

4. Stir in the stock, followed by the cream and white wine or water. Bring to the boil, then reduce the heat to low and allow the sauce to bubble away until it is a little thicker than a pie filling would usually be. From start to finish, the filling should take about 20 minutes to cook.

5. Remove the pan from the heat and leave the filling to cool a little. Preheat the oven to 200°C/400°F/Gas mark 6 and place a metal baking tray in the oven to heat up too. Baking the pie on a preheated metal tray will help you avoid a soggy bottom.

6. Halve the pastry block. Using a rolling pin or a bottle of wine, roll out one of the halves on a clean work surface (sprinkled with a little flour) until it is thick enough to line a 22cm pie dish, or any other ovenproof dish you could line and top with pastry, and big enough to hold the pie filling. Line the dish with the pastry. I've found the easiest way to do this is to slide your rolling pin or wine bottle under the pastry sheet to help you lift the pastry up so you can slide the pie dish underneath. Don't worry if you don't get it first time; it takes practice!

7. Roll out the other half of the pastry block so it is big enough to top the pie. Spoon the pie filling into the dish. 

8. Brush the edges of the pastry with the milk, and lay the second pastry sheet on top. Lift the pie up in the air. This makes it easier to slice the excess pastry off from around the sides of the pie dish. Make a thumbprint pattern around the edge of the pie to seal the pastry. You can use any pastry scraps to decorate the top.

9. Brush the pie lied with milk, and bake it in the oven for 25 minutes until the pastry is golden. Leave the pie to stand for 10 minutes before serving.