Cube steak is a great cut of beef to use in slow cooker recipes. To make this dish, you will need to season the cube steak with salt, pepper, and garlic powder. Dredge the steak in flour, then brown it in a skillet. Transfer the steak to a slow cooker, then add sliced onions and beef broth. Cook on low for 6-8 hours, or until the steak is tender. To make the gravy, whisk together flour and water, then stir it into the slow cooker. Cook for an additional 30 minutes, or until the gravy has thickened. Serve the cube steak and gravy over mashed potatoes or rice for a hearty and comforting meal.