In a slow cooker, whisk together the beef broth, onion soup mix, brown gravy mix, and cream of mushroom soup until well combined.

Pat the beef chuck steaks dry and season both sides generously with the garlic powder.

Place the seasoned beef steaks into the slow cooker, submerging them into the gravy mixture as much as possible.

Cover and cook on Low heat for 6 hours, or until the beef is fork-tender.

In a small bowl, whisk the cornstarch and cold water together to create a smooth slurry.

Stir the slurry into the slow cooker liquid. Cover and cook on High for an additional 20-30 minutes to thicken the gravy.

Serve the beef chops hot, spooning the thickened onion mushroom gravy generously over the meat and sides.