Soak the mushrooms in 100 ml hot water for about 10 minutes. Clean and wash the cauliflower and beans. Divide cauliflower into florets, cut beans in half if necessary. Steam beans, cauliflower and corn on the cob in a little boiling salted water for about 8 minutes.
Drain the bamboo shoots. Peel onions and cut into slices. Cut the chilli lengthwise, remove seeds, wash and cut into rings. Heat oil in a wok or frying pan. Fry the vegetables and chillies for about 5 minutes.
Add mushrooms with soaking water and soy sauce. Bring to the boil briefly and thicken with sauce thickener. Season to taste again. Sprinkle with coriander.