Heat olive oil in a large pot or Dutch oven over medium heat. Add diced chicken and cook until no longer pink. Remove chicken from the pot and set aside.
Add chopped onion to the pot and cook until softened, about 5 minutes. Add minced garlic and cook for 1 minute more until fragrant.
Return chicken to the pot. Stir in black beans, kidney beans, corn, Rotel, tomato sauce, taco seasoning, chili powder, cumin, and cayenne pepper (if using).
Pour in chicken broth and bring to a simmer. Reduce heat to low, cover, and let simmer for 20 minutes to allow flavors to meld.
Stir in softened cream cheese until fully melted and incorporated.
Pour in heavy cream and stir until the soup is creamy.
Season with salt and black pepper to taste.
Serve hot with your favorite toppings.
Notes
For a thicker soup, you can mash some of the beans against the side of the pot.
This soup freezes well. Allow it to cool completely before transferring to freezer-safe containers.
Adjust the amount of cayenne pepper to your preferred spice level.