Chicken & Mushroom Soup

1 cup cooked chicken - shredded
150gm fresh mushrooms - cut fine
1 tbsp butter
1 tbsp flour
4 cup chicken stock
1 large onion chopped fine
salt and pepper to taste

Heat butter in a heavy pan, add mushrooms and fry for 2 minutes. Add flour and blend well. Add chicken stock gradually, stirring briskly. Add chicken and onions and allow soup to simmer for 10-15 min. Season and simmer for another 2 minutes. Serve steaming hot in soup bowls.