Heat olive oil in a large pot or Dutch oven (at least 4-quart capacity) over medium-high heat. Add the diced onion and cook until translucent and soft, about 3 to 4 minutes. They should become slightly see-through and tender. Stir in the minced garlic and cook for another minute until fragrant.

Sprinkle the masa harina evenly over the vegetables and stir constantly for about 1 minute to toast slightly. Pour in about ½ cup of the chicken broth slowly while whisking continuously to prevent lumps from forming.

Stir in the diced green chiles, fire-roasted tomatoes, chili powder, cumin, paprika, enchilada sauce, and the remaining chicken broth. Mix well to combine.

If using raw chicken, add the chicken breasts or thighs, black beans, and sweet corn. Bring to a gentle boil, then reduce heat to low and simmer uncovered, stirring occasionally, for 15 minutes until chicken reaches 165°F internal temperature. If using rotisserie chicken, add beans and corn, bring to simmer, and cook for 5-7 minutes to heat through.

Transfer the cooked chicken to a cutting board. Shred with two forks and return the shredded chicken to the pot. Stir to combine.

Add the softened cream cheese cubes and stir continuously until fully melted and incorporated into the broth, about 2 to 3 minutes. If you see lumps, keep stirring until they dissolve.

Remove the pot from the heat and stir in the freshly grated cheddar cheese. Mix until the cheese has melted completely and the soup is smooth and creamy. Adding cheese off heat prevents graininess.

Taste and adjust seasoning with salt and pepper as needed. Enchilada sauce brands vary in saltiness, so always taste first. Serve immediately with your favorite toppings such as shredded cheese, sour cream, tortilla strips, and fresh cilantro.