Heat the olive oil in a large pot or Dutch oven over medium heat.
Add the diced onion and sauté for 5 minutes until soft and translucent.
Add the minced garlic and cook for 1 minute until fragrant.
Add the chicken breasts, broth, enchilada sauce, diced tomatoes, cumin, and chili powder to the pot.
Bring the mixture to a boil, then reduce heat to low and cover.
Simmer for 15 minutes or until the chicken is cooked through.
Remove the chicken breasts and place on a cutting board, shredding the meat into bite-sized pieces with two forks.
Return the shredded chicken to the pot.
Stir in the black beans and frozen corn, cooking for another 5 minutes to heat through.
Turn off the heat and stir in the shredded cheddar cheese until melted.
Serve hot with optional toppings.