In the bowl of a stand mixer, combine the cream cheese, shredded cheese, chili powder, cumin, and cayenne pepper. Blend until smooth and well combined.
Gently mix in the olives and scallions.
Transfer the cheese mixture to a piece of plastic wrap. Use the wrap to form the mixture into a ball. Wrap with the plastic and refrigerate for one hour.
Meanwhile, add the Doritos to a zipper-top bag. Using a rolling pin, smash the chips into fine crumbs. Transfer the crumbs to a plate.
Roll the chilled cheese ball in the crumbs until completely coated. Serve immediately or chill until ready to serve.
Store covered in the refrigerator for up to one week.