Preparation:

Step 1: Make the Meatloaf Mixture

1. In a large bowl, combine 2 pounds of ground beef, 1 cup of breadcrumbs, 1/2 cup grated Parmesan cheese, 1/4 cup milk, 2 eggs, 1 tablespoon Worcestershire sauce, 1 teaspoon salt, and 1/2 teaspoon black pepper.
2. Mix the ingredients together until well combined. You can use your hands or a spoon, but be careful not to overwork the meat mixture, as this can make the meatloaf tough.
3. Shape the mixture into a loaf and place it in the bottom of the crockpot. Set the crockpot aside while you prepare the onions.

Step 2: Caramelize the Onions

1. In a large skillet, melt 2 tablespoons of butter over medium heat.
2. Add the 2 large thinly sliced onions to the skillet and cook, stirring occasionally, for about 20-25 minutes. The onions should become golden brown and caramelized. Caramelizing the onions brings out their natural sweetness, which pairs perfectly with the savory meatloaf.
3. Once the onions are caramelized, pour 1 cup of beef broth into the skillet and cook for another 5-7 minutes, or until most of the liquid is absorbed. This step infuses the onions with the rich flavor of beef broth, enhancing the French onion theme.

Step 3: Add Onions to the Crockpot

1. Pour the caramelized onions and any remaining broth over the top of the meatloaf in the crockpot, spreading them evenly to cover the meatloaf.
2. Cover the crockpot with the lid and cook on low for 6-8 hours, or until the meatloaf is fully cooked through. The internal temperature should reach 160°F (70°C) when checked with a meat thermometer.

Step 4: Add Swiss Cheese

1. About 10 minutes before serving, top the meatloaf with 8 slices of Swiss cheese. Cover the crockpot again and allow the cheese to melt over the meatloaf. The Swiss cheese adds a creamy and slightly nutty flavor that complements the caramelized onions and beef.

Step 5: Serve

1. Once the cheese has melted, carefully remove the meatloaf from the crockpot and let it rest for a few minutes before slicing.
2. Serve slices of the French Onion Meatloaf with the caramelized onions on top, along with your favorite side dishes such as mashed potatoes, roasted vegetables, or a fresh green salad.