Put the lamb shanks in a hot saucepan with olive oil and fry them well on all sides for about 15 minutes, they should be well browned. Skim off the fat. Salt and pepper the meat. Add anchovies, garlic, rosemary and chilli and fry for 1 minute. Deglaze with wine and let it boil briefly. Pour in the broth and add the tomatoes. Reduce the heat and gently simmer the lamb covered, turning it occasionally, until the knuckles are tender after 1 1/2 hours.