Pat chicken dry with paper towels; sprinkle with 1/2 teaspoon pepper and salt. In a 6-qt. stockpot, heat oil over medium-high heat. Add chicken in batches, skin side down; cook until dark golden brown, 3-4 minutes. Remove chicken from pan; remove and discard skin. Discard drippings, reserving 2 tablespoons.

Add onion to drippings; cook and stir over medium-high heat until tender, 4-5 minutes. Add garlic; cook 1 minute longer. Add broth, stirring to loosen browned bits from pan. Bring to a boil.

Return chicken to pan. Add celery, carrots, bay leaves and thyme. Reduce heat; simmer, covered, until chicken is tender, 25-30 minutes.

Transfer chicken to a plate. Remove soup from heat. Add noodles; let stand, covered, until noodles are tender, 20-22 minutes.

Meanwhile, when chicken is cool enough to handle, remove meat from bones; discard bones. Shred meat into bite-sized pieces. Return meat to stockpot.

Stir in parsley and lemon juice. Adjust seasoning with salt and remaining 3/4 teaspoon pepper. Remove bay leaves.