In a large mixing bowl, add the chicken mince, 1/2 of the grated cheese, 1/2 jar of Napoli Sauce, ham and bread crumbs. Mix until well combined.
Place the puff pastry sheets on a clean bench and slice in half. Divide the mixture into six equal portions. Run the mince mixture down along the long side of each pastry half, shaping mince into a long sausage shape.
Roll up pastry to enclose filling, finishing seam side down. Cut each log into four and place onto a large lined cooking tray.
Mix the egg and milk together in a bowl and brush the sausage rolls with the mixture.
