Refrigerate assembled Halloween Fruit Pizza at 40°F or colder in a shallow airtight container for up to 2 days. Don't freeze it with the fruit and frosting attached because thawing makes both watery. You can freeze the bare cookie crust for 1 month after wrapping it tightly in two layers. Don't reheat assembled slices. For a frozen plain crust, warm it at 300°F for 5 minutes and cool it fully before adding fresh frosting. Discard leftovers if the fruit smells fermented, the frosting turns watery or the berries develop fuzzy spots.