In a large saucepan melt butter. Add onion, carrot and celery. Cook gently 5 min until vegetables are fragrant and tender.
Add chicken. Cook 2 to 3 min until chicken loses its raw appearance.
Sprinkle with flour. Cook 3 to 4 min, browning lightly.
Add chicken stock and bring to a boil. Season with salt and pepper. Cook 15 minute.
Add milk and bring to a boil. Add rice and cook 5 to 10 minute (If soup is thicker than you wish, add a bit more milk, if it is thinner than you like cook uncovered for 5 to 10 min to reduce it.) Taste and adjust seasoning if necessary.
For Cream of Chicken Noodle Soup, add 1 ½ cups (375 ml) cooked noodles instead of the rice.
If you have left over cooked chicken or turkey, add it with the cooked rice in step #5 and omit step #2.