Curried chicken, rice and mushrooms make this a great soup for a cold, rainy day. Sometimes I add cooked cauliflower and broccoli to make it stretch further. Add some grated Cheddar just before serving, if you like.
Place milk in a jar with lid; add flour and shake until well blended. Add milk-flour mixture to chicken stock; stir until boiling. Stir in curry powder and reduce heat to medium low.
Place chicken, onion and celery into a large pan. Cook over medium heat until chicken is cooked and vegetables have softened; add to soup. Stir rice, mushrooms and other vegetables (if using) into the soup. Simmer for 30 minutes, stirring.