Heat 1 tsp of cooking oil in a medium saucepan over medium heat.

Sauté minced garlic and finely chopped onion until tender and translucent.

Shred cooked chicken breasts and add them to the saucepan with the garlic and onion.

Stir until the chicken is combined and heated through.

Set the chicken mixture aside.

In a small mixing bowl, whisk together the red enchilada sauce and masa harina until smooth and lump-free.

Heat chicken broth in a large pot.

Gradually whisk in the masa harina/enchilada sauce mixture into the broth.

Add ground cumin, chili powder, and diced tomatoes (or tomatoes and green chilies) to the pot.

Bring the soup to a slow boil, then reduce the heat.

Add the chicken, onion, and garlic mixture to the pot.

Simmer for 20-30 minutes.

While the soup is simmering, optionally cut corn tortillas into small strips.

Brush the tortilla strips with the remaining cooking oil.

Bake the tortilla strips at 350F for 5-8 minutes, or until lightly browned and crisp.

Serve the soup hot with your choice of toppings, such as a dollop of sour cream, diced avocado, green onions, shredded cheese, and tortilla strips or chips.