Green Beans à la Grecque

• 1 pound green beans
• 1 can tomato concentrate
• 1 pint

Top and tail green beans, and slice them in half lengthwise. Mix tomato concentrate with water, olive oil, and finely chopped onion and garlic. Put beans in a saucepan; pour over tomato-onion mixture, and season to taste with salt and freshly ground black pepper; bring to a boil. Lower heat and simmer gently, stirring from time to time, for ¾ hour, or until sauce has reduced and beans are tende