Preheat your oven to 350 degrees Fahrenheit.
Add your shredded chicken to a bowl and add about 1/4 of a cup of enchilada sauce to your shredded chicken and combine. Taste your chicken to see if it needs any salt and pepper and set aside.
Add avocado oil to a 12-inch cast iron skillet over medium-high heat. Once the oil is hot, add 2 tortillas to skillet and fry for about 15 seconds on both sides, 30 seconds total. Remove tortillas from skillet, add to a plate lined with a paper towel and set aside. Continue this step for the remaining 10 tortillas.
Once all of the tortillas have been fried, drain the oil from the skillet. Pour a little enchilada sauce in the skillet, enough to cover the bottom of the pan. Add four tortillas to the skillet and cover with enchilada sauce, about 1/2 of a cup. Next, top the tortillas with about half of the shredded chicken. Add 4 more tortillas on top of the chicken and cover with another 1/2 of a cup of enchilada sauce. Add the remaining shredded chicken on top of tortillas. Next, add the remaining 4 tortillas on top of the chicken and cover with the remaining enchilada sauce.
Top casserole with shredded cheese, olives, and green onions.
Bake covered for 20 minutes. Remove cover and bake for another 10 minutes.
Serve and enjoy!
