Heat olive oil in a large skillet over medium- high heat. Sear the pork roast on all sides until brown and place in a slow cooker sprayed with nonstick cooking spray.
In a small bowl, combine salt, pepper, onion powder, oregano, chili powder and cumin; sprinkle on top of roast. Top roast with minced garlic and green chiles, then pour chicken broth around the sides. Cover and cook on low for 8-10 hours or high for 5-7 hours. When done cooking, remove pork from slow cooker and shred with two forks.
Preheat the oven to 350 degrees F. Spray a 9x13-inch baking dish with nonstick cooking spray and spread 1 cup of enchilada sauce in the bottom of the pan.
Divide shredded pork and 1 1⁄2 cups cheese evenly between tortillas. Roll up and place seam-side down in the prepared pan. Pour remaining enchilada sauce over the enchiladas and sprinkle remaining cheese on top.
Bake, uncovered, for 30 minutes. Garnish with fresh cilantro before serving, if desired.