Set slow cooker to the Saute function on medium heat. Add olive oil, garlic and onions and saute for about 3 minutes until the onions turn brown and slightly translucent.
Increase the heat to high, then add the lamb and herbs. Sear the lamb on the outside to lock in the flavor of the herbs for 3 to 4 minutes.
Add in the remaining ingredients except for the cabbage. Stir everything together then cook on medium heat for 4 hours.
When 1 hour remains, add the chopped cabbage to the soup and stir. Continue cooking for remaining time.
Season to taste with sea salt & pepper.