Cook sausage according to package directions; cut into small pieces and set aside. In a bowl, combine the green onions, bell pepper, chilies and cilantro; set aside. Spray a 5- or 6-qt. slow cooker with cooking spray. Layer a third of the hash browns, sausage, green onion mixture and cheese. Repeat layers twice. In a large bowl, whisk the eggs, milk, salt and pepper; pour over casserole. Cover and cook on low for 7-8 hours or until a thermometer inserted into the center reads 160°F.