Heat the vegetable oil in a large pot over medium heat.
Add the onion and garlic, cooking until the onion is soft, about 5 minutes.
Pour in the chicken broth and bring to a boil.
In a bowl, whisk the masa harina with 2 cups of water until smooth.
Add the masa harina mixture to the pot, stirring constantly.
Add the enchilada sauce, chili powder, salt, and cumin, stirring to combine.
Reduce the heat to low and simmer for 30 minutes, allowing the flavors to meld.
Add the shredded cheese gradually and stir until melted.
Finally, add the cooked chicken cubes and continue to simmer for another 5 minutes.