Chicken with Seven Vegetables in Pistou Sauce

Name: Chicken with Seven Vegetables in Pistou Sauce (Fondue de poularde au pistou)
Yield: For four people
Cuisine: French
Ingredients: 1 good free-range chicken; 2 litres (3½ pints) strong clarified chicken stock; 2 leeks; 2 carrots; 1 onion; 1 stick of celery; 2 cloves of garlic; 1 fresh fennel twig; 60 g (2 oz) butter; 3 tablespoons olive oil; 2 sprigs of fresh thyme; 1 bay leaf; 3 tomatoes, skinned, deseeded and diced; 2—3 tablespoons pastis; 2 tablespoons flour; 1 tablespoon each basil and tarragon, chopped; 1 tablespoon each basil and tarragon, chopped; a pinch of saffron; 2 tablespoons thick double cream; 3 potatoes, turned into little barrel shapes (the size of garlic cloves); 3 potatoes, turned into little barrel shapes (the size of garlic cloves); salt, freshly ground pepper; salt, freshly ground pepper