Cut the pastry sheets in half. Split the chicken mixture into four. Place one portion of the filling onto the edge of the pastry half. Shape this into a log, roll it and press it to seal it in place. place this onto a lined baking tray, seam side down. Repeat with the rest of the pastry and filling. With a knife, score each roll about 5 times. Place them in the fridge for about half an hour.