Actually mature cremini mushrooms, portobellos (aka portabellas) are extremely large flat-capped mushrooms with a firm, meaty texture and a full flavor. They are often sliced prior to being cooked or added to salads.
Dried portobello slices are versatile and convenient. They will keep in your pantry for a year or longer, they rehydrate easily in boiling water, and once reconstituted can then be cooked in stir fry dishes, added to salads, or otherwise used as you would fresh portobello slices.
Dried mushrooms are a great value. It takes about 5 pounds of fresh mushrooms to create 8 ounces of dried mushrooms.
Dried organic cremini mushrooms (slices) are also available.