Preheat your oven to 375 degrees Fahrenheit. While it's heating up, grab your 9×13-inch baking dish and spray it with cooking spray to prevent sticking.
Set aside about one-third of the bread cubes for later. Place the remaining cubes evenly in the bottom of the prepared baking dish. This will form a sturdy base for your casserole.
Next, take the delicious corned beef and arrange it evenly on top of the bread cubes. Make sure to cover the bread well for maximum flavor.
Drizzle the Thousand Island dressing over the corned beef. Don't be shy—let it soak in to add moisture and taste!
Now, top with the sauerkraut. Allow the tanginess to meld with the other flavors, enhancing the overall profile of your Reuben Casserole.
Combine the two types of cheese—swiss cheese and mozzarella cheese. Sprinkle this cheesy mixture over the top, followed by the reserved bread cubes to create a lovely crust.
Place the casserole in the preheated oven and bake for about 25 minutes. You'll know it's ready when it’s hot all the way through and the cheese is beautifully melted.
Once it’s out of the oven, let it sit for a few minutes to cool slightly. This will make serving easier.
Slice and serve warm, drizzling additional Thousand Island dressing on top for those who want a little extra punch of flavor!
