Start by heating a large pot over medium-high heat. Add the oil and let it warm up for a few seconds. Toss in the diced onion and sauté until translucent, about 3 minutes. Once the onions are soft, add the minced garlic, cumin, oregano, chili powder, and salt. Stir and cook for another 30 seconds to release the fragrance.
Pour in the chicken stock or broth and bring everything to a gentle simmer. Let it bubble lightly for about 20 minutes — this helps the spices and aromatics infuse the broth. In a small bowl, whisk the cornstarch with 2 tablespoons of cold water or broth. Slowly add this mixture to the pot and stir well. Bring it to a light boil for one minute to let it thicken slightly.
Now, reduce the heat and stir in the shredded chicken, drained white beans, thawed corn, and green chiles. Gently add the cream cheese cubes and stir until they begin to melt. Simmer the chili for another 10 to 15 minutes on low heat — make sure it does not boil during this time, as you want it creamy, not curdled.
Once everything is heated through and creamy, turn off the heat. Stir in the lime juice, sour cream, and shredded cheese. Mix until the cheese is fully melted and the chili is smooth. Ladle into bowls and serve with extra sour cream, chopped cilantro, more cheese, and crunchy corn chips if desired.