Treat the family to a classic dish reinvented in a skillet. A pretty patchwork pastry top gives this chicken pot pie a new look. To make the pastry squares, roll out one puff pastry sheet into a 12-inch square, then using a paring knife or kitchen shears to cut it into 16 3-inch squares. To save prep time, shred the chicken and chop the carrots and leek up to two days ahead. Cover and store in the refrigerator.