Preheat the oven to 375°F (190°C).
Season chicken with salt, pepper, chili powder, cumin, garlic powder, and onion powder.
In a skillet, cook the seasoned chicken until no longer pink. Shred the cooked chicken.
In a bowl, mix together the shredded chicken, chopped white onion, chopped green peppers, half of the cheddar cheese, and sour cream.
Pour a small amount of green enchilada sauce into a baking dish.
Fill each tortilla with the chicken mixture, roll it up, and place it in the baking dish.
Pour the remaining green enchilada sauce over the rolled tortillas.
Top with the remaining cheddar cheese and green onions.
Bake in the preheated oven for about 20-25 minutes or until the cheese is melted and bubbly.
Serve hot and enjoy!