Braised Lamb With Prunes without caramel

olive oil 4 lamb fillets (you could also use one large fillet of about 600g if that is all you can get.) 1 small leek , finely diced 3 garlic cloves , crushed[...]

3 -4 tablespoons olive oil 6 lamb shanks 2 large onions , chopped 2 -3 tablespoons chopped fresh garlic (or to taste) 1 1/2 lbs small white button mushrooms 1[...]