White Bean Chicken Chili

3 tablespoons vegetable oil or bacon fat
1 red onion, chopped
1 small carrot, diced small
1 stalk celery, chopped
1 to 2 serrano chiles, seeded and minced
1 1/2 teaspoons ground cumin
1 teaspoon dried oregano
Sea salt
3 cups cooked, diced chicken
5 cups chicken broth, preferably homemade
1 can cannellini beans, rinsed and drained or 1 ½ cups home cooked
1 cup corn
1 medium tomato, diced
juice of 1 lime
½ bunch of cilantro, chopped

In a large heavy soup pot, heat oil over medium heat. Add onion, carrot and celery. Cook until softened, about 8 minutes. Add chiles, cumin, and oregano, and cook another 2 minutes; season with salt. Add broth, beans, tomato, and corn and bring to a boil. Reduce heat and simmer for 20 minutes. Remove from heat and stir in lime juice and cilantro.