These need to be refrigerated because of the egg and dairy content. They will keep in the fridge for 4 days, or wrap them in an airtight container and freeze for up to 3 months. That makes this dessert great to make in advance for special occasions! Once the bars are cool I like to use plastic wrap on the surface of the cheesecake to avoid a skin forming, refrigeration tends to dry out baked goods, so proper wrapping is important.