Combine garlic cloves, extra virgin olive oil, salt, cracked black pepper, lemon zest, and thyme or oregano to create the rub
Massage the rub all over the lamb shoulder
Place the chopped onion on the base of the slow cooker
Add the lamb shoulder to the slow cooker
Pour the beef or chicken stock around the sides
Cook on low until the lamb is fall-apart tender
Finish for 20 minutes in oven until browned.
