Braised lamb shanks with chocolate chilli sauce

Braised lamb shanks with chocolate chilli sauce Ingredients4 lamb shanksSalt and freshly ground black pepperOlive oil1 onion, chopped1 clove garlic, crushed1 red chilli, seeded and finely choppedSmall handful of fresh thyme1 large sprig of rosemary, chopped750ml bottle of red wine1 x 400g can chopped, peeled tomatoes45ml (3 tbsp) balsamic vinegar50g dark chocolate, chopped or gratedPinch dried chilli flakes, optionalMethodTrim and clean the shanks of any gristle and season liberally with salt a...