Preheat the oven to 400°F, creating a warm environment for your chimichangas to bake.
In a large bowl, combine the chicken, cheese, salsa, green chilies, cumin, oregano, and chili powder. Season with salt and pepper to taste.
Lay a tortilla flat, place a portion of the chicken mixture in the center, and fold in the sides, rolling tightly to encase the filling.
Arrange the chimichangas seam-side down on a greased baking sheet, spaced apart for even baking.
Brush the tops with olive oil or spray with cooking spray, then bake for 25-30 minutes until golden brown.
Allow to cool slightly before serving, garnished with sour cream, guacamole, and cilantro if desired.
