For Christmas eve dinner, i cooked a 20lbs, 7 bone prime rib roast. It was cold when i put it in the oven and i thought it would take 14 to 16 hours to cook at 210F, but it only took 5 hours! It came out perfectly with a nice medium rare throughout the entire prime rib, but of course my guests won't be here for another 12 hours. So even though it is perfect, I am not certain of how I should serve it. Once I took it out of the oven, I covered it in foil, let it sit for 30 min and then stuck it in the fridge to cool. This brings me to my question: how should i serve it? I have considered cold beef au jus sandwiches, but that just isn't as good as straight up prime rib. What would be ideal is to heat it back up, but I'm afraid i will ruin it by heating it again. Should I avoid heating it up, or could I bring it up to room temp and then heat it up to 110F or so with the oven set to 200F?