Si Xi Kaufu (Four Happiness Wheat Gluten)

Put wood ear mushrooms into a medium bowl, cover with cold water, and weight down with a small plate. Let soften for 1 hour. Drain and rinse. Trim off and discard any hard spots, then cut into 1" pieces; set aside. Meanwhile, put black mushrooms into a medium bowl, cover with 1 1⁄2 cups cold water, and weight down with a small plate. Let soften for 30 minutes. Strain black mushrooms, reserving liquid. Squeeze black mushrooms dry, trim off and discard stems, then cut into 1" pieces; set aside. Measure reserved black mushroom soaking liquid and add enough water to make 2 cups total. Strain through a fine sieve to remove any grit and set aside.

Heat a 14" flat-bottomed wok over high heat. Swirl in oil, add wheat gluten, and cook, stirring constantly, until oil is absorbed, about 5 seconds. Add peanuts, soy sauce, sugar, mushrooms, and mushroom liquid, cover, and bring to a boil. Reduce heat to low and cook, covered, stirring occasionally, until most of the liquid has been absorbed, about 10 minutes. Serve hot, at room temperature, or chilled, garnished with cilantro (if using).