Slice the bread into thick slices. Spread the mayonnaise in a layer on the bottom, then add a layer of roast vegetables, a layer of stuffing and a sprinkling of cheese.
Add another slice of bread and mayonnaise, then layer the chopped turkey, then spread the cranberry sauce over it, followed by the ham and chutney. Top with the sprouts, then add the potatoes.
Place another slice of bread on top. Wrap this tightly with lots of clingfilm, then set aside in the fridge for at least 2 hours under a heavy weight to compress everything.
Slice into wedges and serve with leftover gravy, if using.