Step 1

Bring a pot of water to a boil; cook chicken in boiling water until no longer pink in the center, 7 to 10 minutes. Remove chicken from water, let cool, and shred.

Step 2

Combine chicken broth, black beans, 1 cup water, and enchilada sauce in a large pot; bring to a boil.

Step 3

Heat oil in a skillet over medium heat; cook and stir onion and garlic until onion is translucent, 5 to 10 minutes. Add onion mixture, chili powder, 1 teaspoon salt, and cumin to the broth mixture.

Step 4

Mix masa, 2/3 cup water, and 1/8 teaspoon salt together in a bowl until evenly combined; form into small balls. Add masa balls and shredded chicken to the broth mixture.

Step 5

Cook until heated through and masa balls are cooked through, 15 to 20 minutes. Stir Cheddar cheese into soup until melted, about 5 minutes. Ladle soup into bowls and garnish with cilantro and sour cream.