If you love a Reuben sandwich, you’ll love this Reuben bake casserole which is basically a deconstructed version of the classic deli sandwich converted for a group. It’s got the tangy, savory, melty goodness I love, just baked into an easy layered dish instead of stacked between slices. Think toasty bread cubes, corned beef, sauerkraut, and cheese all bubbling together like they were meant to be.

There’s never a wrong time to make a Reuben sandwich, but I especially crave them around this time of year. And if I’m not in the mood for stacking and flipping sandwich after sandwich, I take the pieces/parts and make this easy casserole, particularly when I’m feeding a group!

I make corned beef and cabbage every St. Patrick’s Day, because 1) it’s delicious! And 2) because I’m counting on the leftovers the next day. Leftover corned beef is perfect in this easy Reuben casserole, though I’ll happily grab some sliced corned beef from the deli so I can make it year-round. The bread cubes bake up perfectly toasty and chewy in the oven, then I finish everything off with sauerkraut, Swiss cheese, thousand island dressing, and a buttery mustard topping to bring those classic Reuben flavors home.

Helpful Tips & Variations

• Pretzel rolls or Rye bread. Rye bread is traditional for a Reuben, which I love, but I also like using pretzel slider rolls here because after baking with the sauce and kraut, it stays pleasantly chewy with crisp edges instead of getting too soft. That said, feel free to use 8 cups of cubed rye bread instead. Both work!
• Drain your sauerkraut really well. Make sure you ring out all the liquid, or the casserole could get soggy.
• Corned beef options. I’ve made this Reuben casserole bake with home-cooked leftovers, and I’ve made it with deli slices; both are great. You can also use pastrami if that’s what’s in your fridge.
• Low on corned beef? If you’re using leftovers and don’t quite have enough, shred the corned beef instead of chopping it. It spreads out more evenly through the corned beef casserole so every scoop still feels loaded.

How to Make Reuben Bake Casserole Step by Step

Before you start: Gather all of your ingredients and preheat the oven to 400°F. Lightly spray a 9×13-inch baking pan with nonstick spray.

Layer the casserole: Add 4 cups small-cubed pretzel slider buns to the pan in an even layer. Evenly scatter 1 lb. chopped corned beef over the bread, then spoon on 1 cup fully drained sauerkraut in an even layer.

Drizzle over ½ cup Thousand Island dressing, then add 2½ cups shredded Swiss cheese, and finish with the remaining 4 cups cubed pretzel buns.

Add the butter topping: Stir together 5 Tbsp melted unsalted butter, 1 Tbsp spicy brown mustard, and 2 tsp minced dried onion flakes in a small bowl until combined. Pour the butter mixture evenly over the bread cubes in the casserole dish.

Bake: Place the Reuben bake casserole into the preheated oven and bake uncovered for 20-25 minutes, until the top is nicely toasted and the cheese is fully melted. Serve warm, and enjoy!

Serving Suggestions

I can easily see this Reuben bake casserole served for brunch, lunch, or dinner with no complaints. It’s delicious with something crunchy on the side, so pickle spears are always a yes, and fried pickles are a fun and tasty alternative. Air fryer onion rings are another great match because the crisp, salty bite plays so well with the cheesy casserole. If I want something fresher on the plate, my cauliflower salad or some roasted broccoli are perfect.

How to Store

• Fridge. This Reuben bake casserole is best served fresh for the best texture. If you do have leftovers, let them cool, then cover the pan tightly or transfer to an airtight container. Store in the fridge for up to 3 days.
• Freezer. To freeze, transfer to a freezer-safe container for up to 2 months. Thaw overnight in the fridge before reheating.
• Reheat. To reheat, warm individual servings in the microwave in 30 second bursts until hot, or reheat in a 350°F oven covered with foil for about 15 minutes. Uncover for the last few minutes if you want the top to crisp back up.

More Reuben-Style Recipes

• Reuben Pretzel Sliders: All the classic Reuben flavors packed into baked pretzel rolls—these are a game day favorite!
• Reuben Quesadillas: Turn leftover corned beef into a quick, cheesy meal with sauerkraut, Swiss, and Thousand Island dressing.
• Hot Reuben Dip: Transform a Reuben sandwich into a warm, creamy dip that’s easy to make.
• Reuben Pinwheels: A quick appetizer that’s perfect for St. Patrick’s Day.

I hope you love this delicious and easy recipe – be sure to give it a review below! Also don’t forget to follow Belly Full on TikTok, Facebook, Instagram, Pinterest, and YouTube!