I had a small piece of chuck roast in the freezer left over from cutting a large roast up. I put it in the Crock Pot (still frozen) on High for a few hours and then turned it to Low to cook until super tender and it shred easily. I used random salt-free spices and hot sauces. We had some bread in the freezer so I defrosted and on the side that would touch the pan I both buttered and spread with mayo over (fabulous combo), The other side I spread with mayo. Once the bread was in the pan I added cheese and the shredded beef and more cheese. I put a lid over the pan to help the cheese melt. Once golden on bottom, flipped and repeated. I had mine open-faced, my hubby ate his second one for breakfast which I put in toaster oven wrapped in foil for 15 min at 400 degrees. Them 5 min uncovered at 400. I wonder if you could do these in advance and freeze for future re-heating?!?!?!