These are actually dried shiitake mushrooms. They look like they’ve seen better days, but they revive fast, becoming a delicious, flavor- absorbing vegetable that adds color and texture to soups, noodle dishes, and ground meat dishes such as Vietnamese Meat Loaf. A 15- to 20-minute immersion in warm water brings them back to their former glory. You’ll need to trim away and discard their woody stems. They keep for ages; then transfer them to a jar and have them within easy reach in the pantry.