Fricassee of Chicken Legs with Lyonnaise Potatoes

Name: Fricassee of Chicken Legs with Lyonnaise Potatoes
Cuisine: United Kingdom
Ingredients: 500 ml chicken stock or water; 2 bay leaves; Salt and freshly ground black pepper; 1 tablespoon chopped flat-leaf parsley; Sprig of savory or thyme; 100 ml white wine vinegar; 6 whole chicken legs, cut into thighs and drumsticks; 50 g butter; 1 large onion, finely chopped; Good Splash of vegetable oil; 2 tablespoons olive oil; 2 garlic cloves, crushed; 200 ml white wine; 125 g butter; 2 onions, thinly sliced; 3 garlic cloves, thinly sliced; 200 ml double cream; 6 large Maris Piper potatoes