Keto Reuben Chaffle Sandwich
Published September 22, 2019 • Updated March 14, 2026
This post may contain affiliate links. See my disclosure policy.
I almost left the caraway seeds out of this reuben chaffle, and I'm glad I didn't. They're the thing that pulls the batter toward actual rye bread, and once you pile on corned beef, swiss, sauerkraut, and homemade thousand island, this tastes like the real thing.
I’ve been making chaffles since they first blew up, and this keto reuben chaffle sandwich is the one that made me stop thinking of them as a bread substitute. It tastes like a Reuben. Not like a keto version of a Reuben. The caraway seeds are doing the heavy lifting here. I almost left them out during testing because I wasn’t sure they’d come through in such a small amount of batter, but they pull the whole chaffle toward rye bread in a way that surprised me.
The chaffle itself is sturdy. I’m not talking about a flimsy waffle that falls apart when you look at it. I loaded mine with extra corned beef, a full slice of swiss, a generous pile of sauerkraut, and it held. Go heavy on the corned beef because this chaffle is thick enough to take it. If you’ve made my keto pizza chaffle or my keto sandwich chaffle bread, you already know the texture I’m talking about. Firm edges, slight give in the center, golden and crisp.
One thing I changed after making this a few times: I pan-press the assembled sandwich in a skillet for about 90 seconds per side. The microwave melts the cheese fine, but pressing it in a hot pan with a little butter gives you that deli-style crust on the outside. It’s the difference between “good enough” and “I’m making this again Friday.” If you like that same toasty finish, my keto grilled cheese uses the same technique.
This works for meal prep, but you have to be smart about it. Keep the sauerkraut separate or it will waterlog the chaffle within an hour. I store the chaffles stacked with parchment between them, corned beef and swiss in a separate container, sauerkraut in its own jar. When I’m ready to eat, I toast the chaffle in the air fryer for 2-3 minutes and it comes out crispy again. One of my readers, Heather, confirmed this exact system works for a full week of lunches, and she’s right. If you’re looking for more low carb lunch ideas that hold up for meal prep, my Italian keto sliders and carnivore sandwich both travel well too.
Pastrami works here if you prefer it over corned beef. I’ve made it both ways. Pastrami has a smokier, peppery edge that plays differently with the sauerkraut, but it’s still a legitimate Reuben swap. The thousand island stays the same either way.
How to Make a Reuben Chaffle
The key is getting your waffle maker hot enough before the batter goes in. I set mine to medium-high and let it preheat for at least 2 minutes. If the batter spreads and sits there without sizzling, it’s not hot enough and you’ll end up with a soft, pale chaffle that won’t hold toppings.
Mix the batter just until combined. The mozzarella will clump a little and that’s fine. Don’t overmix or the chaffle gets dense instead of crispy. Pour it into the center and let the lid do the work of spreading it out. I cook mine for 5-7 minutes. Yours might be different depending on your waffle maker, but you want golden brown edges and a firm center.
For the assembly, I used to just microwave the corned beef and swiss together. That works. But if you want the full deli experience, press the finished sandwich in a buttered skillet until the outside is toasted and the cheese is melting through. It takes 90 seconds per side and the texture difference is worth it. If you like sandwiches with that kind of crispy exterior, try my portobello sandwich or sandwich bowl for more keto lunch ideas.
Ingredients
1 egg -
½ cup mozzarella cheese
-
2 tablespoons almond flour
-
2 tablespoons low-carb thousand island dressing
-
1/4 teaspoon baking powder
-
1/4 teaspoon caraway seeds
-
2 slices of corned beef
-
1 slice swiss cheese
-
2 tablespoons sauerkraut
Step by Step Instructions
Step by Step Instructions
Preheat
Preheat waffle maker to medium high heat.
Mix the chaffle batter
In a small bowl, whisk together egg, mozzarella cheese, almond flour, 1 tablespoon thousand island dressing, caraway seeds and baking powder.
Add to waffle maker
Pour the reuben chaffle mixture into the center of the waffle iron. Close the waffle maker and let cook for 5-7 minutes or until waffle is golden brown and crisp. If using a mini dash waffle maker, only pour half the batter onto the waffle iron. This recipe will make two mini chaffles.
Make a waffle
Remove chaffle from the waffle maker. Repeat with remaining batter if using a mini dash waffle maker.
Assemble sandwich
On a piece of parchment paper, lay down the corned beef and top with a slice of swiss cheese. Heat in the microwave for 20-30 seconds until cheese starts to melt. Remove from microwave. Spread remaining tablespoon of low-carb thousand island dressing on each chaffle, layer the heated corned beef and swiss cheese and top with sauerkraut and remaining chaffle.
Nutrition disclaimer
The nutrition information provided is an estimate and is for informational purposes only. I am a Doctor of Pharmacy (Pharm.D.); however, this content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always consult your physician or other qualified health provider before making any lifestyle changes or beginning a new nutrition program.
Your Macros. Your Recipes. Calculated in 60 Seconds.
Get personalized keto macros and instantly see which recipes fit your targets. No more guessing what to eat.
Get My Macros + Recipes →Frequently Asked Questions
Can I use pastrami instead of corned beef?
I've made this with both. Pastrami brings a smokier, peppery flavor that changes the sandwich feel a bit, but it works. I actually prefer pastrami when I'm craving something closer to a New York deli style. The sauerkraut and thousand island balance out the stronger spice. Use the same amount you'd use for corned beef.
What's the difference between Russian dressing and thousand island for a Reuben?
I use thousand island because it's what I always have on hand, but the traditional Reuben actually calls for Russian dressing. The difference is small. Russian is tangier with more horseradish kick, and thousand island is sweeter with pickle relish. I've tested both on this sandwich and my preference is thousand island because the sweetness plays better against the sauerkraut. Either works.
Can I freeze these chaffles for later?
I freeze them all the time. Let the chaffles cool completely, then stack them with parchment paper between each one and seal in a freezer bag. They keep for about a month. When I'm ready to use them, I go straight from freezer to air fryer at 375 for 3-4 minutes. No thawing needed. They crisp back up almost like fresh.
How do I keep the chaffle from getting soggy once assembled?
Keep the sauerkraut separate until you're about to eat. I learned this the hard way. Sauerkraut will waterlog the chaffle within an hour if you assemble too early. For meal prep, I store chaffles, meat, and sauerkraut in separate containers. Toast the chaffle in an air fryer for 2-3 minutes right before assembling and it comes out perfectly crispy.
What can I use instead of almond flour?
I've tested coconut flour as a swap. It absorbs more moisture, so I use about 1 tablespoon of coconut flour for every 2 tablespoons of almond flour. The texture is slightly different (a little denser) but it still crisps up in the waffle maker and holds toppings fine. For a completely nut-free option, this is my go-to substitution.
Should I grind the caraway seeds or leave them whole?
I've done both. Whole seeds give you bursts of rye flavor when you bite into one, which I like. But one of my readers, Lilly, grinds hers before adding them to the batter and says the rye flavor distributes more evenly through the whole chaffle. I tried it her way and she's right. If you want every bite to taste like rye bread, grind them. If you like the occasional pop of flavor, leave them whole.
How many net carbs are in this keto reuben chaffle sandwich?
Mine comes in around 5-7 grams of net carbs for the full sandwich, depending on your thousand island dressing and sauerkraut brand. I use a low carb thousand island that's about 1g per tablespoon. The chaffle itself is the lowest-carb part. Check your dressing label since that's where the carbs can sneak up.
Can I use a different cheese in the chaffle batter?
I've swapped in swiss (to match the sandwich filling) and it works well. My reader Lilly does a half mozzarella, half swiss mix in the batter and loves it. Cheddar works too, especially if you're using these chaffles as burger buns. The melt and texture change a little with each cheese but the chaffle still holds its structure. I'd avoid softer cheeses like brie since they don't crisp the same way. If you want a totally different keto sandwich base, bell peppers work for an even lower-carb option.
If you miss a good Reuben sandwich with lots of sliced corned beef, melted swiss cheese, and a pile of sauerkraut, I’ve got good news. This chaffle version brings it all back.
The chaffle batter gets caraway seeds and a splash of thousand island dressing to mimic rye bread. Cook it a little longer and it crisps up just like the real thing.
Any waffle maker works for chaffles. 
Traditional Reubens use corned beef, but pastrami works too. I go with corned beef.
Yes, 
Does it have to be the mini waffle iron or will a regular one work?
Pastrami reads better with the caraway.
I've been skeptical about chaffles as actual sandwich bread and this one mostly won me over. The caraway seeds actually pull toward rye. One fix though: the corned beef goes on cold right from the fridge and kills the heat, warm it in the pan thirty seconds first.
Don't lift the waffle iron lid before the steam slows down. I opened it at the first beep and the chaffle stuck to both sides and came out in pieces. Give it an extra minute or two until the steaming mostly stops. Comes out clean. I stirred in a small spoonful of cream cheese with the batter and it gave the chaffle more structure, which helps once you pile on the corned beef and everything else. One thing I'd adjust: the thousand island in the batter is subtle, so I've been adding a small drizzle on top at assembly too.
Maria, cream cheese in the batter is something I do in plain chaffles and somehow never brought it over to this one. And the extra drizzle at assembly is so obvious I can't believe I don't already do it. Fixing that next batch.
The crust gets almost brittle when you add an extra tablespoon of mozzarella, and that's what makes it hold up under the sauerkraut instead of going soft by the second bite. Found this on batch three by accident. Keep the heat at medium-high the whole cook, not just to start and then pull back. Do both and it won't collapse when you pick it up.
Extra mozzarella for that brittle hold, I never thought of that. I still pull the heat back out of habit and the whole thing collapses every time.
Stopped ordering reubens at restaurants a month into keto and barely thought about it. Made this last week and realized I'd been thinking about it wrong. The corned beef and sauerkraut carry the whole thing.
The sauerkraut really does pull the whole thing. Keep it separate until you're actually eating though, Brandon - it waterlogged my chaffle within an hour the first time I assembled too early.
putting thousand island IN the batter. I had questions. I was wrong.
That ingredient reads like a recipe error, I know. Mixing it into the batter is what distributes the reuben flavor all the way through.
My husband watched me pour the batter into the waffle iron and then asked if the corned beef came from a deli counter. The caraway seeds in the batter are the thing that does it, turns out.
Caraway seeds in a hot waffle iron smell like actual rye bread. Once that's in the air, the whole thing reads as deli.
Batch six or seven and those caraway seeds still pull it toward actual rye bread every time.
Six or seven batches in and it still tracks, good to hear. Whole seeds if you haven't tried that yet. Better rye hit than ground.
Brought these to a potluck last weekend and watched someone spend like five minutes trying to figure out what kind of bread she was eating. She kept insisting it tasted like the deli rye from the place she grew up near. The caraway seeds are doing something real in that batter. I was a little nervous bringing chaffle sandwiches to people who had no idea what a chaffle was, but I came home with an empty plate.
That 'five minutes trying to figure out the bread' is what I put the caraway seeds in for. Empty plate at a potluck is the whole goal.
My husband is the Reuben guy in our house and I've tried making them at home before with mixed results. He took one bite of this and said it tasted like the deli near where we used to live, which I was not expecting from a chaffle. I think it's the caraway seeds doing that, they pull the whole thing toward actual rye bread in a way I didn't anticipate. I almost left them out because I wasn't sure I had any, but found them in the back of the spice cabinet and went for it. My only note is that the chaffle is a little more fragile than regular bread when you press the sandwich together, so I was careful with assembly. The corned beef and sauerkraut ratio felt just right though. Adding this to the lunch rotation for sure.
Yep, that's the one. Skip the caraway and it just tastes like a hot sandwich. I don't even bother pressing mine, just stack it.
The reuben is the one sandwich I've genuinely mourned since going keto two years ago. I tried wraps, low-carb tortillas, even a cabbage version, and none of them got close because the bread is half the point of a reuben. What finally changed it for me was the caraway seeds. I almost skipped them thinking they were optional, but I added them anyway, and the chaffle stopped tasting like a waffle and started tasting like something you'd actually build a sandwich around. Piled on the corned beef, swiss, sauerkraut, and the thousand island, pressed it together, and had to just stand there for a second. I keep a list of foods I've made peace with giving up, and I quietly took this one off it.
Taking it off the list is the only review that matters. The stand-there-for-a-second moment is the one I was going for.
My dad used to take me to this deli every Sunday and I always ordered the Reuben. When I went keto I just quietly accepted that it was off the table. The caraway seeds in this chaffle are doing something I wasn't prepared for.
Those Sunday trips are a real thing to lose. Glad the caraway seeds landed.
Made this six or seven times now, and I finally got it where I want it. I drain the sauerkraut really well before assembling. Keeps the chaffle from going soft in the middle. The caraway seeds are non-negotiable at this point. Skip them and it's just a good egg waffle with corned beef. Keep them and it actually reads like a reuben.
Draining it is better than just keeping it separate, honestly. I should update the instructions with that. And yeah, without the caraway it's just corned beef on an egg waffle. Good, but not a reuben.
Brought these to a St. Patrick's Day get-together and set them next to actual deli sandwiches without saying anything. My friend who eats everything kept reaching for the chaffle ones because she said the caraway made them taste 'more reuben-y' than the real ones. I'm still a little proud of that.
You should be proud of that. She wasn't being polite, she had an actual deli sandwich right next to it.