Place lamb shanks in slow cooker. Combine all other ingredients (except for cornflour and water) in a bowl and whisk to combine. Pour sauce over lamb. Cook for 8 hours on low. When cooked remove lamb shanks. Mix cornflour with a little water and use to thicken the sauce to your desired consistency. Serve with mashed potato or other vegetables of your choice.

(My apologies for the messy plate in the photo, my husband barely gave me a chance to take the photo let alone clean the plate as he was too eager to eat it - first time I have cooked him lamb as I don't eat it)