YES! In fact, I highly recommend that you do. As with many stews, the braised short ribs will continue to develop flavor over time. I also love that after refrigeration, the excess fat that has rendered will float to the top and solidify. To remove it, simply scrape a spoon across it before reheating. This is an ideal celebration or dinner party dish mainly because it does so well being made ahead. On the day of, all you need to do is reheat the short ribs and whip up a quick batch of polenta.