1. Place chicken in a large stock pot (8 quarts). Peel 3 of the carrots and cut into 3 pieces. Trim 2 of the celery ribs and cut into 3 pieces. Peel and quarter one of the onions. Peel garlic; cut 3 cloves in half. Add prepped carrots, celery, onion and garlic to pot with chicken. Add enough cold water to cover, about 2-1/2 quarts. Stir in 1 teaspoon each of the salt and dill. Bring to a boil over high heat and then reduce heat to medium. Simmer for 1-1/2 hours, occasionally skimming any foam from top.
2. Meanwhile, peel and slice remaining 3 carrots and slice 2 ribs celery. Chop remaining onion and slice remaining 3 cloves garlic.
3. Carefully remove chicken from pot to a large bowl and let rest until cool enough to handle. Strain broth into a large bowl; discard soggy vegetables. Remove fat from top of broth. Once chicken has cooled, remove meat from bones and discard skin and bones. Chop meat into bite-size pieces.
4. Heat olive oil in soup pot over medium heat. Add sliced carrot, celery and onion. Cook 3 minutes. Add sliced garlic; cook an additional minute. Stir in remaining 2 teaspoons salt, remaining 1/2 teaspoon dried dill, the tomatoes and pepper. Add defatted broth back to pot and bring to a simmer. Simmer 6 minutes, until vegetables are tender.
5. Meanwhile, bring a large pot of salted water to boiling. Add noodles to boiling water and cook 6 minutes.
6. Once vegetables are tender, add chicken back to pot. Remove half of soup (8 cups) and transfer to a freezer-safe container. Save for another meal. Drain and freeze half of noodles along with soup (in a separate container). Stir remaining noodles into soup in pot and serve immediately.