Place chicken in a large stockpot and cover with water by about 1–2 inches. Add the carrots, celery, onion, garlic, and season liberally with salt. Bring to a boil, reduce heat, and simmer for 1–2 hours. Skim off any foam or scum from the top as it cooks.

Using tongs, remove the chicken from the pot and transfer it to a bowl.

Return the stock to a low boil (rapid simmer) for 20 minutes to reduce it further. It will deepen in color.

Once the chicken is cool enough to handle, remove and discard the skin. Pick the meat from the bones and shred or cut the meat into bite-sized pieces. Reserve carcass for another use. Set the meat aside.

Strain the broth through a fine-mesh sieve into a large bowl. Discard the solids. Wipe out the pot and return it to the stove.

Heat the neutral oil in the pot. Add the onion, carrots, and celery and cook for 5–7 minutes. Season with salt, pepper, paprika, and crushed red pepper. Cook for 1 minute until fragrant.

Pour in the prepared broth. You should have enough to cover the ingredients in the pot fully. Supplement it with water if needed. Taste and season once more.

Bring to a boil and then reduce heat and simmer for 15–20 minutes or until the carrots are almost fork-tender.

Bring the soup back to a boil. Add the elbow macaroni to the soup (note: you can cook it separately if you don't like pasta swelling). Cook for 8–10 minutes until pasta is al dente.

Reduce heat to low and stir in spinach. Let simmer for 3–4 minutes. Turn off the heat.

Ladle soup into bowls and enjoy!