Cut the bean curd into strips. Soak the dried mushrooms in boiling water for 30 minutes, then drain, reserving the soaking liquid, and squeeze out excess water. Remove and discard the stems and cut in half.
Heat a wok over high heat, add the oil and heat until very hot. Stir fry the mushrooms for 35 seconds, then add 150ml of reserved mushroom liquid and bring to the boil. Add the bean curd, salt, sugar and rice wine, and stir very gentle to blend well. Braise for 2 minutes, making sure there is enough liquid to prevent the bean curd sticking to the wok, then sprinkle with the sesame oil.
Combine the cornflour and soy with enough of the reserved liquid to make a paste. Add to the sauce and simmer to form a clear, light glaze.
