10- 15 minutes. Pleurotus eryngii is a kind of wild mushroom, which contains some toxins and needs proper treatment before cooking. Soak in clear water for about 2 hours, then blanch with boiling water 1-2 times, each time for 2 minutes. This will remove most of the toxins. After toxin treatment, mushrooms can continue to cook. Usually, it takes about 10- 15 minutes to cook mushrooms. Cook until the mushrooms become soft and discolored, and the mushroom meat is cooked.