Easy Keto Reuben Casserole

If you love a classic Reuben sandwich, you already know how addictive that combination of corned beef, sauerkraut, Swiss cheese, and creamy dressing can be.

But sometimes I want all those flavors without making sandwiches.

That’s when this Easy Keto Reuben Casserole comes in.

It’s warm, cheesy, creamy, tangy, and incredibly satisfying. You get tender pieces of corned beef, sauerkraut, melted Swiss cheese, and a creamy Russian-style dressing baked together until bubbling around the edges.

And the best part?

There’s no bread to deal with.

I first made this on a chilly weekend when I had some leftover corned beef in the refrigerator.

I had originally planned to make Reuben sandwiches, but I was out of low-carb bread.

Rather than make another trip to the store, I decided to turn everything into a casserole.

I layered the ingredients into a baking dish, covered it with cheese, and put it in the oven.

A little while later, the whole kitchen smelled like a classic deli.

When I pulled it out, the cheese was melted and bubbling, the sauerkraut was warm and tangy, and the corned beef had picked up all those delicious flavors from the sauce.

Everyone loved it.

Now it’s one of my favorite ways to use leftover corned beef—and honestly, I sometimes make corned beef specifically so I can make this casserole afterward.

Prep Time: 10 minutes
Cook Time: 25 minutes
Total Time: About 35 minutes
Servings: 6

Why You’ll Love This Keto Reuben Casserole

• Low-carb and keto-friendly
• All the classic Reuben flavors
• No bread required
• Creamy and cheesy
• Great for leftover corned beef
• Easy weeknight dinner
• Excellent meal-prep option
• Family-friendly comfort food
• Ready in about 35 minutes

Ingredients

• 1½ lbs cooked corned beef, chopped
• 2 cups sauerkraut, well drained
• 1½ cups shredded Swiss cheese
• ½ cup shredded mozzarella cheese
• ½ cup mayonnaise
• ¼ cup sour cream
• 2 tablespoons sugar-free ketchup
• 1 tablespoon Dijon mustard
• 1 teaspoon Worcestershire sauce
• ½ teaspoon garlic powder
• ¼ teaspoon black pepper
• 1 tablespoon chopped fresh parsley, optional

How to Make Easy Keto Reuben Casserole

Step 1: Preheat the Oven

Preheat your oven to 190°C (375°F).

Lightly grease a 9×13-inch baking dish.

Step 2: Prepare the Sauerkraut

Place the sauerkraut in a fine-mesh strainer.

Press out as much liquid as possible.

This step matters because excess liquid can make the casserole watery.

If your sauerkraut is particularly wet, gently squeeze it with paper towels.

Step 3: Prepare the Corned Beef

Chop the cooked corned beef into bite-sized pieces.

You can use leftover homemade corned beef or deli-style corned beef.

If you’re using deli corned beef, choose thicker slices and chop them into pieces rather than using very thin slices.

Step 4: Make the Reuben Sauce

In a bowl, combine:

• Mayonnaise
• Sour cream
• Sugar-free ketchup
• Dijon mustard
• Worcestershire sauce
• Garlic powder
• Black pepper

Stir until smooth.

Taste and adjust the mustard or seasoning if needed.

This creamy sauce gives the casserole that familiar Reuben-style flavor.

Step 5: Layer the Casserole

Spread half of the corned beef into the bottom of the prepared baking dish.

Add half of the sauerkraut.

Drizzle or spoon over half of the sauce.

Sprinkle with half of the Swiss cheese.

Repeat the layers with the remaining corned beef, sauerkraut, sauce, and cheese.

Finish with the mozzarella.

Step 6: Bake

Cover the casserole loosely with foil and bake for 15 minutes.

Remove the foil.

Continue baking for another 10–15 minutes, until the cheese is completely melted and bubbling around the edges.

For a golden top, broil for 1–2 minutes at the end.

Watch it carefully.

Step 7: Rest

Remove the casserole from the oven and let it rest for approximately 5–10 minutes.

This allows the sauce to thicken slightly and makes serving easier.

Garnish with fresh parsley if desired.

My Best Tips

Drain the Sauerkraut Well

This is the biggest secret to avoiding a watery casserole.

Use Good Swiss Cheese

Swiss cheese provides that unmistakable Reuben flavor.

For extra cheesiness, add a little mozzarella along with it.

Don’t Skip the Dijon

The mustard adds a little sharpness that balances the richness of the cheese and dressing.

Use Leftover Corned Beef

This casserole is one of my favorite ways to turn leftover corned beef into a completely different meal.

Can I Use Pastrami?

Absolutely.

Pastrami gives the casserole a slightly smokier, pepperier flavor.

It’s a delicious alternative to corned beef.

Can I Use Turkey?

Yes.

Turkey pastrami or sliced turkey can work if you’re looking for a lighter version.

The flavor won’t be exactly the same as a traditional Reuben, but it will still be delicious.

Can I Make This Without Sauerkraut?

You can, although sauerkraut is an important part of the classic Reuben flavor.

If you don’t enjoy it, substitute:

• Sautéed cabbage
• Thinly sliced cooked cabbage
• Shredded Brussels sprouts

Can I Make My Own Russian Dressing?

Absolutely.

For a quick homemade version, mix:

• ½ cup mayonnaise
• 2 tablespoons sugar-free ketchup
• 1 tablespoon Dijon mustard
• 1 tablespoon sour cream
• 1 teaspoon Worcestershire sauce
• A pinch of garlic powder
• A pinch of paprika

Adjust the seasoning to taste.

Can I Use Thousand Island Dressing?

Yes.

Traditional Reubens are often served with Russian or Thousand Island-style dressing.

For keto, choose a low-carb dressing and check the label for added sugar.

Can I Add Caraway Seeds?

Definitely.

A small amount of caraway seeds adds a wonderful deli-style flavor that pairs beautifully with sauerkraut.

Start with ½ teaspoon.

Delicious Variations

Bacon Reuben Casserole

Add ½ cup cooked, crumbled bacon for extra smoky flavor.

Spicy Reuben Casserole

Add sliced jalapeños or a little hot sauce to the dressing.

Mushroom Reuben Casserole

Sauté sliced mushrooms and layer them into the casserole.

Extra Cheesy Reuben

Use Swiss, mozzarella, and a little provolone together.

Reuben Chicken Casserole

Replace the corned beef with shredded cooked chicken and add a little extra seasoning.

Can I Make This Keto?

Yes.

The casserole is naturally low in carbohydrates, but check the labels on your ketchup, dressing, Worcestershire sauce, and corned beef.

Use sugar-free ketchup or a low-carb Russian/Thousand Island dressing to keep the carbohydrate count down.

Can I Make It Gluten-Free?

The basic casserole can be gluten-free, but always check your corned beef, Worcestershire sauce, ketchup, and other packaged ingredients.

Can I Make This Ahead?

Yes.

Assemble the casserole, cover it tightly, and refrigerate for up to 24 hours.

When you’re ready to bake it, allow an extra 5–10 minutes of cooking time because the casserole will be chilled.

Storage

Store leftovers in an airtight container in the refrigerator for up to 3–4 days.

How to Reheat

Reheat individual portions in the microwave.

For the best texture, place the casserole in a covered oven-safe dish and warm at 175°C (350°F) until hot.

Can I Freeze It?

Yes, although the sauerkraut and creamy sauce may soften slightly after freezing.

Cool completely, portion into freezer-safe containers, and freeze for up to 2 months.

Thaw overnight in the refrigerator before reheating.

What to Serve With Keto Reuben Casserole

Because this casserole is rich and cheesy, I like pairing it with something crisp and fresh.

Try:

• Cucumber salad
• Green salad
• Roasted broccoli
• Green beans
• Pickles
• Coleslaw
• Roasted cauliflower
• Simple cabbage salad

A few crunchy dill pickles on the side are especially good.

Nutritional Information

Approximate per serving:

• Calories: 470
• Protein: 32g
• Fat: 34g
• Total Carbohydrates: 7g
• Fibre: 2g
• Net Carbohydrates: 5g

Nutrition values are estimates and will vary depending on the corned beef, cheese, dressing, and other ingredients used.

Frequently Asked Questions

Can I use leftover corned beef?

Yes! That’s one of the best reasons to make this casserole.

Why is my casserole watery?

The sauerkraut probably wasn’t drained thoroughly enough. Press out as much liquid as possible before adding it.

Can I use deli corned beef?

Yes. Thick-cut deli corned beef works very well.

What cheese can I use instead of Swiss?

Try provolone, mozzarella, Monterey Jack, or a combination.

Can I make this without mayonnaise?

You can replace some or all of the mayonnaise with sour cream or softened cream cheese, although the flavor will be slightly different.

Can I make it spicy?

Absolutely. Add hot sauce, cayenne pepper, jalapeños, or spicy mustard.

Is this good for meal prep?

Yes. It reheats beautifully and is easy to portion into individual containers.

Final Thoughts

This Easy Keto Reuben Casserole is one of those recipes that makes leftovers feel exciting.

The corned beef is savory and tender.

The sauerkraut brings that wonderful tang.

The creamy dressing ties everything together.

And the melted Swiss cheese on top makes the whole dish feel wonderfully indulgent.

I love making this after a holiday meal when there seems to be a mountain of leftover corned beef in the refrigerator.

Instead of eating the same dinner twice, you get something completely different.

And there’s something especially comforting about pulling a bubbling casserole from the oven and smelling that familiar Reuben combination of beef, mustard, sauerkraut, and melted cheese.

No bread.

No complicated assembly.

Just all the good parts of a Reuben in one cozy dish.

Serve it with crisp pickles and a simple salad, and you’ve got an easy low-carb dinner that feels like comfort food from your favorite neighborhood deli.

And if you happen to find yourself going back for one more cheesy scoop before the leftovers make it into the refrigerator, I won’t blame you.

I probably would too. 🥩🧀🥬