Heat 1 tablespoon extra virgin olive oil in a large pot over medium heat. Add the celery, onion, fennel, and carrots. Season with 1 to 2 teaspoons of kosher salt. Add black pepper to taste. Cook, stirring often, for 10 minutes until the vegetables soften.
Add the garlic and cook for 1 minute until fragrant.
Simmer the soup:
Add the chicken to the pot and toss to coat. Cover with 6 cups of chicken broth and bring to a boil. Reduce the heat and simmer, uncovered, for 30 minutes. Taste and adjust the salt and pepper to taste.
Cook the pasta:
Bring a medium pot of salted water to a boil. Once boiling, add the dry elbows and cook for 6 minutes. Drain.
Finish the soup:
Add the frozen peas, cooked pasta, and lemon juice to the soup. Simmer for 5 minutes. Taste and season, then remove from the heat.
To serve:
Ladle the soup into bowls and enjoy!
Notes
Note 1: You will need about 5 cups of mixed vegetables in total. You can adjust the quantities of different vegetables depending on your preferences. For example, if you're not a fan of carrots, increase the amount of celery or add a red bell pepper instead.Note 2: I recommend starting with 1 teaspoon kosher salt and adding more to taste as you work on the soup. Depending on your store-bought chicken broth, you may need more or less salt.