1 large sweet onion, peeled and sliced into thin rings
3 lbs bone-in chicken breasts, skin removed and cut in half (or 2 lbs of boneless breast halves)
1 tbsp olive oil
20 garlic cloves, light smashed and peeled (about 2 large heads of garlic)
2 tsp sea salt
1 tsp dried thyme
1 tsp paprika
1 tsp fresh-ground black pepper
Lightly oil the bottom of a 6-quart slow cooker. Evenly place the sliced onion along the bottom.
Place the chicken into a large mixing bowl and drizzle with olive oil. Add the peeled & smashed garlic cloves and toss to combine. Sprinkle the seasonings across the top of the chicken-garlic mixture and toss until chicken is well coated with seasonings.
Transfer the chicken-garlic mixture to the slow cooker and cover. Cook on low for 4-5 hours, or high for 2-3 hours.