To store leftovers, let the tortellini cool completely, transfer to an airtight container, and store in the refrigerator for up to 3 days. It can also be frozen for up to 3 months. To reheat, microwave or bake until heated through. Watch cooking time to avoid overcooking the tortellini and use plenty of sauce to keep the dish moist. You can also add vegetables or use different sauces for variations.