You sure can! Using a Crockpot is a good idea if you want to keep the dip warm throughout the duration of a party. Simply prepare the spinach dip mixture as the recipe instructs, then spread it in a Crockpot rather than a baking dish. Add the shaved parmesan on top if you wish. You can warm it through either on high or low, but you'll want to keep an eye on it either way. Once it's heated through completely, turn the Crockpot down to the warm setting. On high, it will take 20-30 minutes. On the low setting, it will take about an hour. Give it a good stir before serving it to your guests.