In a heavy 3 quart saucepan, saute onions and parsley in butter until onions become transparent. Add beans, season with salt and pepper, vegetables juice, and water. Cover and cook until beans are tender, about 35-40 minutes.
In a small saucepan, heat milk, and whisk in flour and cook for 30 seconds. Pour this into soup after beans are tender, and cook for 5 to 10 minutes, until soup is slightly thickened.
To serve: garnish with sour cream and parsley.
NO MORE GRAY BEANS
To ensure a bright green bean color in your favorite recipe, try blanching the beans in briskly boiling water to which 1 generous teaspoon of salt has been added. Cook the beans in this water for 2030 seconds, until the color changes to bright green, and immediately plunge the beans in ice water to stop the cooking, and set the color. You can use the beans for crudite, or continue to cook them with a quick saute.