1.Toss the lamb in combined flour, salt and pepper; shake off any excess.
2.Heat a large, non-stick frying pan over medium-high heat. Add the oil and shanks to the pan; cook until lamb is browned all over. Transfer lamb to the bowl of the slow cooker.
3.Reduce the heat to medium and add the onion, garlic and oregano to the same pan; cook, stirring, for 3 or 4 minutes until the onion is starting to soften. Add the red wine and simmer for 1 minute before adding the wine mixture to the slow cooker. Stir in the stock and undrained tomatoes.
4.Turn slow cooker onto the high setting. Cook, with the lid on, for 2 hours. Remove the lid and cook for a further 2 hours or until tender. Add the olives in the last 30 minutes of cooking. The lamb is cooked when it is buttery soft and falling off the bone. The sauce should be quite rich in flavour; season to taste.
5.Sprinkle lamb with parsley and serve with mashed potato and beans, if desired.
Suitable to freeze. Not suitable to microwave. The shanks can also be cooked on low for 8 hours. If you aren’t home to remove the lid halfway through cooking, remove it as soon as you can. Or, remove the shanks from the liquid and transfer the liquid to a saucepan; simmer, uncovered on the stove until reduced and thickened.