Frozen berries are one of the best items to keep in the freezer for quick desserts, smoothies and more. When berries are in season, buy extra and freeze right in the container. Once they are frozen, transfer to plastic bags. But if you missed this step last summer, be assured berries from the supermarket’s freezer are a reliable and juicy alternative. Use any frozen berry to make this luscious and quick parfait. If berries are very tart, add sugar until they reach the desired sweetness.