Peel the jerusalem artichokes. Peel and halve the garlic cloves. In a large pan, mix lemon juice and olive oil. Add the garlic halves, jerusalem artichokes and saffron threads. Add water to cover, and bring to boil over moderate heat. Add the chicken, season to taste, and cook 1 1/2 hours. Add basil, check seasonings, and cook another 10 minutes. Garnish with pine nuts, and serve with cooked rice.