Heat oil in a non stick pan. Slice onion and add. Slice garlic, and add and sauté. Chop green chillies and add along with mushrooms and salt and cook. Slice bread thinly and toast in the oven at a low temperature until crisp. Add pepper powder, green chillies, cream and cheese and mix. Arrange the toasts on a serving platter, spread the mushroom mixture in the centre and serve immediately.