Step 1

Preheat the oven to 220C/200C Fan/Gas Line a baking tray with baking paper. Unroll the pastry and cut in half. Re-roll one half, wrap in foil and set aside or freeze for another time. Cut the remaining piece into 10–11 long strips.

Step 2

Place the pastry strips on the lined tray, weaving in and out to make a criss-cross lattice. Turn a 1 litre/1¾ pint pie dish or tin upside-down on top of the lattice and cut around it, leaving roughly 2cm/¾in on each side to allow for shrinkage.

Step 3

Remove the dish or tin, brush the pastry with a little milk and bake for 15–20 minutes, or until well risen and golden-brown.

Step 4

To make the filling, heat 1 teaspoon of the oil in a large frying pan over a high heat. Season the sliced beef all over with freshly ground black pepper. Fry the beef for just 2 minutes, or until lightly browned, and transfer to a plate.

Step 5

Return the pan to the heat, add the remaining oil and fry the onion and mushrooms for 5–6 minutes, stirring regularly until lightly browned. Sprinkle over the flour and garlic powder (or crushed garlic) and stir well.

Step 6

Slowly add the stock, just a little at a time, stirring all the time. Add the tomato purée, Worcestershire sauce and dried herbs and bring to a simmer.

Step 7

Cook for 5 minutes, stirring regularly, then stir in the beef, heat through for a few seconds and immediately remove from the heat. (As the beef is very lean, it is important not to overcook it at this point.)

Step 8

Spoon the beef filling into the pie dish (see Recipe Tip below), top with the cooked puff pastry and serve.