Chicken and Leek Pie

Step 1: Trim off the dark green ends and root, then cut each leek in half across its length. Cut each piece in half lengthways. Remove the outer 5 to 6 layers, keeping them together, and lay them flat. Cut those layers in half lengthways, then into 1.8 cm / 3/4-inch squares. Cut the inner core into 2 cm / 0.8-inch pieces.

Step 2: Melt half the butter in a large pan over high heat. Add the chicken, salt and pepper. Cook until the surface changes from pink to white while the inside is still raw. Remove the chicken to a bowl with a slotted spoon, leaving the butter and chicken juices in the pan.

Step 3: In the same pan, cook the bacon for 1 minute. Add the leek, celery and garlic. Cook for 5 minutes, until the celery is softened. Do not let the leek brown; lower the heat if needed.

Step 4: Add the wine and simmer rapidly over high heat, stirring, until it is mostly evaporated.

Step 5: Lower the heat to medium and add the remaining butter. Once it melts, sprinkle the flour across the surface rather than adding it all in one spot. Stir for 1 minute.

Step 6: While stirring, slowly pour in the stock. The mixture will thicken into a thick sauce once combined. Add the mustard, cream, thyme, bay leaves, salt and pepper, and stir to combine. Add the chicken and all the juices from the bowl.

Step 7: Increase the heat and stir to combine. Once the mixture comes to a simmer, reduce the heat to medium-high. Simmer for 5 minutes, stirring regularly, or until the sauce reaches the thick, creamy consistency you want in the finished pie.

Tip: The sauce will not thicken further in the oven, so adjust its consistency now.

Step 8: Remove the pan from the stove and cool the filling for 1 hour.

Step 9: Preheat the oven to 200°C/375°F (180°C fan-forced). Use a 1.5 litre / 1.5 quart baking pan or 4 to 5 ramekins of about 350 ml / 12 oz each.

Step 10: If needed, semi-thaw the puff pastry. Brush the edge of one sheet with egg white, then overlap it by 0.5 cm / 0.2 inch with the other sheet to join them. Use the back of a spoon to press and smear the pastry together, hiding the seam.

Tip: Semi-thawed pastry is easier to handle than fully thawed pastry.

Step 11: Cut out the pie lid, using the dish as a guide.

Step 12: For optional extra-puffy edges, cut strips from the remaining pastry and place them around the rim of the dish if it has a thick rim.

Step 13: Fill the pie dish with the cooled filling and smooth the surface. Brush the pastry strips on the rim with egg white, if using them, then cover the pie with the puff pastry lid.

Tip: If you are not using pastry strips, skip brushing the rim with egg white so the lid does not stick too firmly to the baking dish.

Step 14: Brush the lid with egg yolk and cut a small X in the middle.

Step 15: Bake for 45 minutes or until the surface is deep golden brown. Rest for 5 minutes, then serve.