Gently sauté onion and garlic in a large pan until just tender, add the beef and brown all over. Stir in the flour and cook for 2-3 minutes, then gradually stir in the stock, tomato purée, potatoes and Worcestershire sauce. Bring to the boil then simmer for approximately 20 minutes until the potatoes are cooked, stirring frequently, season to taste. Allow to cool.
Preheat oven to 200⁰C (180⁰C for fan assisted ovens) Gas Mark 6.
Roll out just over half the pastry and use to line a pie dish approx. 20cm/8” in diameter allowing any excess to hang over edges. Place the cooled meat mixture in the dish and spread evenly over the pastry. Roll out remaining pastry large enough to cover the pie, brush the base pastry borders with beaten egg, then top with the second piece of pastry, pressing edges firmly together all round. Trim off edges with a sharp knife, flute if desired. Make a small hole in the top of the pie to allow the steam to escape. Brush top with beaten egg and bake for 30 minutes or until pastry is golden brown. This pie may be eaten hot or cold.
For top tips on protecting you and your family when preparing raw meat and poultry, visit Food Safety in the Home.