In a large pot or Dutch oven, heat a small amount of oil over medium heat. Sauté the chopped onion until softened, about 3-5 minutes, then add the minced garlic and cook for another minute until fragrant.

Stir in the chili powder, cumin, salt, and black pepper, cooking for about 30 seconds until aromatic.

Pour in the chicken broth, diced tomatoes (undrained), black beans (rinsed and drained), and drained corn. Bring the mixture to a simmer.

Add the shredded cooked chicken to the pot and continue to simmer for at least 15-20 minutes, allowing the flavors to meld.

Taste the soup and adjust seasonings as needed, adding more salt, pepper, or spices to your preference.

Ladle the hot soup into bowls and serve immediately. Garnish with your favorite toppings such as tortilla chips, shredded cheese, sour cream, diced avocado, and fresh cilantro.