Preheat your oven to 375°F (190°C) and grease a 9x12-inch casserole dish with olive oil.

Heat 2 tablespoons of olive oil in a skillet over medium heat. Add chopped onion and a pinch of salt, sautéing until softened.

Stir in minced garlic, chili powder, and cumin and cook for an additional minute.

Add 2 cups of shredded cooked chicken into the skillet, mixing thoroughly. Remove from heat.

In a separate bowl, combine 1 cup of salsa verde and ½ cup of sour cream until smooth.

Spread ¾ cup of the creamy salsa mixture on the bottom of the greased casserole dish. Layer half of the corn tortillas, half of the chicken mixture, 1 cup of salsa verde, and top with ½ cup of cheese.

Repeat with the remaining tortillas, chicken mixture, salsa, and another ½ cup of cheese.

Bake for 15-20 minutes until the cheese is melted and bubbly.

Allow the casserole to rest for 10-15 minutes before slicing.