Place the turkey carcass, bones from wings and drumsticks, neck bone, onion, carrots and garlic in a 15x10x1-in. baking pan coated with cooking spray. Bake, uncovered, at 400° for 1 hour, turning once., Transfer the carcass, bones and vegetables to an 8-qt. stockpot. Add 4 qts. cold water; set aside. Pour remaining cold water into baking pan, stirring to loosen browned bits. Add to pot. Bring to a boil. Reduce heat; cover and simmer for 3-4 hours. , Cool slightly. Strain broth; discard bones and vegetables. Set stockpot in an ice-water bath until broth cools, stirring occasionally. Cover and refrigerate overnight. , Skim fat from broth. Cover and bring to a boil. Reduce heat to a simmer. Meanwhile, in a Dutch oven, bring 3 qts. water to a boil. Add noodles and carrots; cook for 4 minutes. Add celery; cook 5-7 minutes longer or until noodles and vegetables are tender. Drain; add to simmering broth. Add cubed turkey; heat through. Stir in the parsley, salt, thyme and pepper.