Straw mushrooms are oval or egg-like mushrooms, in the same way as the young horse mushrooms, and are cultivated to just reach the opening stage to keep their pleasing shape. Grown mostly on composted rice paddy straw, hence the nickname paddy straw mushrooms, they are produced mainly in Hong Kong, Thailand, Taiwan and Indonesia. Soft and squidgy, these mushrooms are very delicate and are brined and canned upon harvesting.