1. In the slow cooker, stir together the soup, broth, and gravy mix.
2. Season the pork chops on both sides with the ranch mix, garlic powder, and pepper and add them to the soup mixture in the slow cooker.
3. Cover the slow cooker and cook on low for 7 hours or on high for 4 hours.
4. Remove the pork chops from the slow cooker and put them on a plate.
5. Whisk the cornstarch-and-water mixture into the liquid in the slow cooker and let cook for several more minutes, stirring occasionally, until the mixture thickens to a good gravy consistency.
6. Serve the pork chops with the sauce spooned over the top.
