Chili's Chicken Enchilada Soup

1/4 cup vegetable oil
1 1/2 cups onion, diced
1 tsp cumin
1 tsp chili powder
1 tsp garlic powder
1/4 tsp cayenne pepper
1 cup Masa Harina (found in the Mexican isle of your grocery store)
8 cups chicken broth
1 cup of canned crushed tomatoes
1 (15oz) can RED enchilada sauce
8oz Velveeta cheese, cubed
3 cups chicken, shredded (I buy a rotisserie chicken from the deli and pull the chicken off the bones)
Toppings
Tortilla strips
Sour cream

Heat a large (12 quart preferably) pot over medium high heat and add the vegetable oil.
Once hot, add the onions and spices and saute until onions are soft and translucent, about 5 minutes.
In a separate bowl combine the Masa harina with 4 cups of chicken broth and whisk until combined.
Pour mixture into the large pot, and stir constantly, cooking, for 2-3 minutes. Mixture will become thick.
Pour in the remaining chicken broth, enchilada sauce and crushed tomatoes, stir and bring to a boil.
Add the cubed Velveeta cheese, and stir until melted. Stir in the shredded chicken.
Serve topped with sour cream and tortilla strips.