Preheat the slow cooker if necessary; see the manufacturer's instructions. Lightly oil a soufflé dish, 14 cm (5½ inches) in diameter and 9 cm (3½ inches) high, and base-line with nonstick baking paper, checking first that the dish will fit in the slow cooker pot. Stretch each bacon rasher with the flat of a large cook's knife, until half as long again, and use about three-quarters of the rashers to line the base and sides of the dish, trimming to fit.
Put the stuffing mix in a bowl, add the cranberries and mix with boiling water according to the pack instructions. Heat the oil in a frying pan, add the onion and fry for 5 minutes, stirring, until softened. Set aside. Finely chop the turkey slices in a food processor or pass through a coarse mincer.
Mix the stuffing with the fried onion, chopped turkey and egg. Season well and spoon into the bacon-lined dish. Press flat and cover with the remaining bacon rashers. Cover the top of the dish with foil and lower into the slow cooker pot. Pour boiling water into the pot to come halfway up the sides of the dish. Cover with the lid and cook on high for 5–6 hours or until the juices run clear when the centre of the meatloaf is pierced with a knife.
Lift the dish out of the slow cooker pot using a tea towel and leave to cool. Transfer to the refrigerator to chill overnight until firm. Loosen the edge of the meatloaf with a knife, turn out on to a plate and peel off the lining paper. Cut into thick slices and serve with salad and spoonfuls of cranberry sauce or Beetroot Chutney (see