Preheat oven to 200C.

Heat olive oil in a medium saucepan and cook leek for about 3 minutes or until soft. Add flour and stir for 1 minute.

Combine stock, milk and cream in a jug, gradually stir into leek mixture and cook, stirring constantly, until mixture boils and thickens. Stir in chicken and parsley then spoon mixture into a lightly greased ovenproof dish (six-cup capacity) and cool.

When cold, brush rim of dish with a little extra milk and place puff pastry over filling, trim to fit dish and decorate edges.

Rest in the fridge for 15 minutes then brush top with a little extra milk and cut a small slit in the pastry for steam to escape.

Bake for 20-40 minutes or until pastry is golden.

*Raw chicken breasts can be poached in two cups' chicken stock for 10 minutes then rested in the stock for 10 minutes before chopping.