1. Prepare the Meatloaf

Preheat your oven to 350°F and lightly grease a 9×13-inch baking dish. In a large mixing bowl, combine the ground beef, eggs, milk, shredded cheddar cheese, quick oats, chopped onion, and salt. Mix just until everything is evenly combined.

2. Bake the Meatloaf

Press the meat mixture evenly into the prepared baking dish. Bake for 40–45 minutes, or until the meatloaf is fully cooked.

3. Drain the Grease

Carefully remove the baking dish from the oven and drain any excess grease. This helps keep the casserole rich and flavorful without becoming greasy.

4. Add the Glaze

In a small bowl, stir together the ketchup, brown sugar, and yellow mustard until smooth. Spread the glaze evenly over the top of the cooked meatloaf.

5. Add the Mashed Potatoes

Spread 6–7 cups of prepared mashed potatoes evenly over the glazed meatloaf. If desired, brush the mashed potatoes with ½ stick of melted butter for extra richness and beautiful browning.

6. Add the Cheese

Sprinkle 2 cups of shredded cheddar cheese evenly over the mashed potatoes, covering the entire casserole.

7. Finish Baking

Return the casserole to the oven and bake for 20–25 minutes, or until the cheese is completely melted and bubbly.

8. Broil for a Golden Top

For a beautifully browned finish, broil the casserole for 2–3 minutes, watching closely to prevent the cheese from burning.

9. Let It Rest

Allow the casserole to rest for 10 minutes before slicing and serving. This helps the layers set, making it easy to cut clean, sturdy slices that hold together perfectly. 🍽️