Prepare the slow cooker: Lightly coat the inside of your slow cooker with non-stick spray or line it with foil for easy cleanup. This step prevents sticking and ensures smooth removal after cooking.
Mix the meatloaf: In a large mixing bowl, combine the ground beef, French onion soup mix, breadcrumbs, eggs, milk, garlic powder, and shredded mozzarella. Gently mix with your hands or a spoon until evenly blended. Avoid overmixing to keep the meatloaf tender.
Shape and place: Form the mixture into a loaf shape and place it in the prepared slow cooker. Make sure it sits centered so it cooks evenly.
Add topping: Spread the ketchup evenly over the top of the loaf to create a flavorful glaze as it cooks.
Cook: Cover and cook on low for 6–7 hours or high for 3–4 hours, until the meatloaf is cooked through and reaches an internal temperature of 160°F (71°C). The slow cooker method keeps the meat incredibly moist and flavorful.
Rest and serve: Once done, let the meatloaf rest for about 5 minutes before slicing. This allows the juices to redistribute for a perfect, tender texture. Serve warm with mashed potatoes or steamed vegetables for a complete meal.
