Preheat: Preheat oven to 375°F (190°C).
Prepare the filling: Heat olive oil in a pan. Add onion and garlic; then cook for 2–3 minutes. Add shredded chicken, chili powder, cumin, salt, and pepper. Stir well.
Add sauce: Next, pour in a few spoonfuls of enchilada sauce and mix until the chicken is coated.
Assemble enchiladas: Meanwhile, place a small amount of chicken filling inside each tortilla, roll tightly, and place seam-side down in a baking dish.
Add sauce and cheese: Then, pour the remaining sauce evenly over the rolled tortillas and sprinkle with cheese.
Bake: Finally, bake for 15–20 minutes, or until the cheese is melted and bubbly. Garnish with fresh cilantro and serve with sour cream.