Fresh thyme sprigs, to garnish
Filling
2 tblsps olive oil1 To make filling, heat oil in a large frying pan over a medium to high heat. Add chicken in four batches. Cook, stirring, for about 3 minutes, or until lightly browned. Remove.
2 Add leek, pancetta, garlic and thyme to same pan. Cook, stirring occasionally, until leek is soft.Add wine. Boil until reduced by half. Return chicken to pan with cream, stock and cornflour blended with water. Bring to boil, stirring, until slightly thickened. Transfer to a large bowl. Refrigerate until cold.
3 Sandwich two pastry sheets together, with egg brushed over pastry in between layers. Cut out two circles, 11½cm in diameter. Repeat with remaining pastry. Reserve scraps.
4 Divide filling among four ovenproof ramekins (1½-cup capacity). Brush edge of ramekins with egg. Place pastry circleson top to cover filling, allowing pastry to over-hang by 1cm. Press sides in firmly to seal. Cut a small cross in the top of each pie, to allow steam to escape. Brush with egg. Place on an oven tray.
5 Cut out eight leaf shapes from pastry scraps. Arrange on top of pies. Brush with egg.
6 Cook in a hot oven (200C) for about 20 minutes, or until puffed and golden. Remove. Stand for 5 minutes.
7 Garnish with thyme sprigs.Tip: Filling can be made up to two days ahead. Keep, covered, in the fridge. Cook pies just before serving.