Place chicken in the slow cooker, together with oil, garlic, Italian seasoning, sea salt and pepper. Toss well to coat.
Pour tomato sauce on top then cook on LOW for 8 hours or HIGH for 4 hours.
Add the shredded Mozzarella and cook on HIGH for an additional 20-30 min, or until melted.
Sprinkle with fresh chopped herbs and serve over zucchini noodles.