Once you've opened a jar of sundried tomatoes in oil, they'll need to be stored in the fridge. Make sure they are covered with oil, topping up with some extra virgin olive oil if needed. They can last for a few months, but do check for colour changes, mold or a musty smell before using them. Alternatively, you can drain the oil away and puree the sundried tomatoes, then freeze in ice cube trays before transferring to a container or ziplock bag in the freezer. This sun dried tomato paste keeps for at least 6 months and is a great easy addition to sauces and pastas.