Preheat the oven to 200℃ (180℃ fan)/400°F/gas mark 6. Cut 300-400g (10-12oz) turkey into bite size pieces. Remove the casing from 125g (4oz) chorizo and thickly slice or cut into chunks.
Heat 2 tbsp olive oil in a large saucepan and gently fry 1 sliced onion until softened. Add the chorizo and fry until the fat is released and the onions are beginning to colour.
Stir in 200g (7oz) sliced mushrooms and cook until beginning to soften, then add the turkey.
Sprinkle over 3 tbsp plain flour and slowly stir in 300ml (10 floz) milk and 300ml (10 floz) stock or leftover gravy. Bring to a gentle boil. stirring constantly. Transfer to a large pie dish.
Roll out the pastry a little bigger than the pie dish or unroll the pastry if using ready rolled pastry). Cut a strip of about 2cm (1in) wide pastry from around the edge of the pastry
Brush the edge of the dish with a little beaten egg and stick the strip of pastry to the dish. Brush the top of the pastry strip with a little more beaten egg.
Working quickly (the pie filling is hot and will start to melt the fat in the pastry) lift the remaining pastry over the dish and press down the edges with a fork to seal. Brush the top of the pastry with beaten egg and make a small slit in the centre to allow steam to escape.
Place the pie on a baking sheet and bake in the centre of the oven for 20-30 minutes or until the pastry is crisp and golden.
Nutrition information is calculated usingan online nutrition database - is approximate and is meant as a guideline only. (It does not include seasoning with salt and pepper.)