I’ll be honest. When Christina first suggested turning a Reuben sandwich into a casserole, I looked at her like she’d lost it. Sauerkraut? In a baking dish? With eggs poured over bread cubes? The whole concept sounded like something you’d find in a 1970s church cookbook, and not in the charming way.

But she kept pushing, and one Saturday afternoon I finally caved. We had pastrami in the fridge from a deli run earlier that week, a jar of sauerkraut that had been sitting there for who knows how long, and half a loaf of rye bread that was a day past its prime. So I figured, fine, let’s just see what happens.

What happened was my new favorite casserole. Not even exaggerating. The rye bread soaked up this creamy custard mixture and turned almost savory-bread-pudding-like, the Swiss cheese melted into every layer, and the sauerkraut brought this tangy bite that cut through all the richness. I stood at the counter eating it straight from the dish before it even cooled down. Christina didn’t say “I told you so” out loud, but the look on her face said it plenty.

Now I make this at least twice a month, and it’s become the thing I bring to every gathering where people ask me to “bring that casserole again.”

Why This Version Works

A lot of Reuben casserole recipes online are basically just corned beef and sauerkraut dumped into a pan with some cheese melted on top. That’s fine if you want something quick, but it doesn’t capture what actually makes a Reuben sandwich great. This version builds layers. You’ve got cubed rye bread on the bottom that soaks up a custard made from eggs, milk, Russian dressing, and mustard. That’s the backbone. Then comes the pastrami (split into two layers so every bite gets some), the drained sauerkraut and pickles for crunch and tang, and 3 1/2 cups of Swiss cheese woven through the whole thing. The rye breadcrumb topping gives you a golden crust that shatters when you scoop into it. Every component of the sandwich is here, just restructured into something that feeds eight people from one pan.

Ingredients with Notes

Ingredient	Amount	Swaps & Notes
Rye bread	7 slices	Marble rye or seeded rye both work great. Day-old bread is actually better here
Pastrami	1 1/3 lb, chopped	Corned beef is the classic swap. Either one works
Swiss cheese, shredded	3 1/2 cups (divided)	Gruyere if you want something nuttier, but Swiss is the move
Sauerkraut	1 can (14.5 oz)	Drain it thoroughly. Squeeze it dry with paper towels
Pickles, chopped	1 cup	Dill pickles. Don’t use sweet pickles here
Russian dressing	6 tbsp	Thousand Island works as a swap. Similar flavor profile
Yellow mustard	4 tbsp	Dijon if you want a sharper, more complex kick
Eggs	3 large	Room temperature is better for mixing into the custard
Milk	1 1/2 cups	Whole milk for the best texture. 2% is fine too
Caraway seeds	2 tsp (divided)	These are optional but they really sell the rye flavor

Optional: caramelized onions, chopped bacon, or a few dashes of hot sauce if you like a little heat.

Step-by-Step

Step 1: Preheat and prep your baking dish.

Set your oven to 350F (175C) and let it come up to full temperature before anything goes in. Grab a 9×13 inch baking dish and give it a coat of nonstick spray or a thin layer of butter. While the oven heats, get all your ingredients out on the counter, open the cans, and chop the pastrami and pickles. This is a layered build, so having everything ready to go before you start makes the whole assembly smooth and fast. Probably 10 minutes of prep total.

Step 2: Cube the bread and make the breadcrumbs.

Take 5 slices of your rye bread and cut them into rough 2-inch cubes. They don’t need to be perfect. Spread those cubes across the bottom of your baking dish in a single layer, covering as much surface as you can. Then take the remaining 2 slices and pulse them in a food processor until you’ve got fine breadcrumbs. If you don’t have a food processor, just tear the bread into tiny pieces by hand or use a grater. Set those crumbs aside in a small bowl. They’re your crunchy topping for the end.

Step 3: Build the first layer of fillings.

Scatter half of your chopped pastrami over the bread cubes. Then add the drained sauerkraut on top of that. And I mean really drain it. Squeeze it between paper towels or press it hard in a colander. Soggy sauerkraut is the number one reason Reuben casseroles turn out watery (trust me, I learned this the hard way on round one). Spread the chopped pickles over the sauerkraut and sprinkle 1 teaspoon of caraway seeds across the layer. Press everything down gently with your hands so it starts to compact and settle. You want good contact between layers.

Step 4: Add the cheese and remaining pastrami.

Spread 2 cups of the shredded Swiss cheese over the sauerkraut and pickle layer, pushing it all the way to the edges so no corner gets left out. Then scatter the rest of your pastrami on top. Press it all down again. Top with the remaining 1 1/2 cups of Swiss cheese and the second teaspoon of caraway seeds. This double-cheese approach means you get melty Swiss in the middle AND on top. It matters more than you’d think.

Step 5: Whisk the custard and pour it over everything.

In a mixing bowl, whisk together the milk, eggs, Russian dressing, and yellow mustard until it’s smooth and fully combined. This custard is what turns a pile of deli ingredients into an actual casserole. Pour it slowly and evenly over the whole dish, making sure to hit the corners and edges. Then take a spatula or the back of a spoon and gently press down on the top layer to help the liquid soak into the bread below. You should see it seeping down through the layers. Give it 5 minutes to absorb before the next step if you have the patience.

Step 6: Top with breadcrumbs and bake.

Sprinkle those reserved rye breadcrumbs evenly over the top of the casserole. Cover the dish tightly with aluminum foil. You want a good seal to trap the steam and cook everything through evenly. Slide it onto the middle rack and bake covered for 45 minutes. Then pull back the foil (careful with the steam) and bake uncovered for another 10 to 15 minutes until the cheese is bubbling, the breadcrumbs are golden brown, and the edges are starting to pull away slightly from the pan. The whole kitchen will smell like a deli at this point.

Step 7: Rest before serving.

Pull the casserole out and let it sit on the counter for 5 to 10 minutes before cutting into it. This resting time lets everything firm up so you get clean slices instead of a soupy mess. I know it’s tempting to go right in. Resist. Use a sharp knife or a big spoon to scoop portions. The layers should hold together with the bread, custard, and melted cheese all working as one.

What to Serve It With

This casserole is heavy and rich, so you want something fresh and light next to it. A simple coleslaw with a vinegar-based dressing is my go-to. It cuts through the richness the same way coleslaw works on a pulled pork sandwich. Roasted potatoes are another solid option if you want something warm on the side. I’d avoid anything too heavy or creamy since the casserole already has plenty of that going on. If you’re in the mood for more beefy casseroles after this, the Philly Cheesesteak Casserole hits a similar comfort food note, and the Ground Beef and Pasta Casserole is great for nights when you want something a little simpler.

Storage and Leftovers

Still a Skeptic?

I get it. I was one too. But there’s something about this casserole that converts people. The tangy sauerkraut, the salty pastrami, the melted Swiss pulling in strings when you lift a scoop out of the dish. It’s a Reuben sandwich that grew up and decided to feed the whole table. Christina still brings up the face I made when she first suggested it. Honestly, it’s fair. I was wrong. Make it once and you’ll stop doubting it too.