Slice a roughly 3cm lid off the top of the loaf. Scoop out most of the bread from the loaf and lid, leaving about a 1cm layer (you can use the scooped-out bread for croutons or in another recipe).

Combine the mayonnaise and mustard, then spread 2 tbsp over the inside of the loaf, and 1 tbsp inside the lid. Spoon most of the cranberry sauce into the lid, followed by half the spinach, the crispy onions, and half the turkey. Arrange the rest of the turkey in the base of the loaf, followed by the rest of the cranberry sauce, the pigs in blankets, stuffing and remaining spinach. Top the loaf with the stuffed lid, press down lightly, then tightly wrap and chill for at least 3 hrs. Slice into four or six wedges to serve.