Using a sharp knife, chop chicken into bite-size pieces. Transfer chicken to a paper towel-lined plate to blot some of the excess oil, set aside.
Heat a large pot over medium heat, add 2 tablespoons olive oil. When oil is hot, add mirepoix and a pinch of salt. Sauté until onions are translucent, 3-5 minutes.
Add chicken, chicken broth, and water to pot and stir. Partially cover and simmer for about 30 minutes, until chicken is cooked through.
Add rice, cumin, and 1 teaspoon salt to pot and stir. Cover and cook for 15-20 minutes more.
Uncover, remove from heat and let stand 5 minutes. Skim excess oil and stir in lemon juice. Season soup to taste with salt.
Ladle soup into large bowls and enjoy!
