Turkey Broth: Put the turkey carcass in your slow cooker at Low with an onion, celery stalk, a carrot, salt and pepper, bay leaf, 1/2 tsp poultry seasoning, 2 tsps chicken powder and water. Cook on Low overnight. Next morning, strain the both and pour it back in the slow cooker. Remove turkey meat from bones, set meat aside. Soup: In the slow cooker with the broth, add onions, garlic, carrots, celery, thyme, salt and pepper. Cook at High for 4 hours; add reserved turkey and noodles. Cook another 1/2 hour.