Leftover prime rib makes my favourite sandwiches. You could substitute other shredded beef, or deli roast beef if you like. I also used leftover mushrooms and onions but it is quick to make them up fresh as well.
Looking for a fun and delicious way to use up some holiday dinner leftovers? Try our Leftover Makeover French Toast recipe, and discover a new breakfast favourite using turkey and cranberry sauce from the night before!