¼ cup extra-virgin olive oil
1 onion, diced
2 stalks celery, diced
2 carrots, diced
2 garlic cloves, minced
1 teaspoon lemon zest
2 tablespoons lemon juice
1 bay leaf
½ teaspoon kosher salt
¼ teaspoon freshly ground black pepper
6 cups chicken broth
3 cups cauliflower rice
1 pound cooked chicken, shredded or diced
Heat the oil in a stockpot or Dutch oven over medium-high heat. Add the onion, celery, carrot and garlic, and cook, stirring frequently, until the vegetables begin to soften, about 3 minutes. Stir in the zest, juice, bay leaf, salt and pepper.
Lower the heat to medium, cover, and cook just until the vegetables are soft, about 3 minutes more.
Stir in the broth and cauliflower rice, raise the heat to medium-high, and bring to a boil. Lower the heat again to medium or medium-low, and let simmer, uncovered, until the vegetables are very tender, 5-8 minutes more.
Stir in the chicken and cook, stirring, just until heated through. Serve hot.