Braised Lamb with sauce

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[...]

6 lamb shanks 1 large onion (sliced) 2 garlic cloves , minced 1/2 tablespoon ground ginger 1/2 teaspoon turmeric 1/2 teaspoon cumin powder 1/2 teaspoon[...]