These keto lemon bars strike that perfect balance of bright, tangy lemon flavor and a smooth, creamy filling on top of a buttery shortbread crust. If you’ve been missing a truly good low carb lemon bar, this one delivers.
They’re not quite a “dump and stir” recipe—but don’t let that scare you. The extra step is what gives these bars their rich, silky texture, and it’s absolutely doable (and worth it, I promise.)
If you don’t want to read the origin story of these keto lemon bars, please feel free to use the Jump to Recipe button on the top right of the page.
Lemon bars have always been one of my absolute favorite desserts. They are the thing I’m most likely to gaze longingly at through the glass at a bakery or coffee house – and sometimes I give in and have one.
I’m never really sorry until the next day when I wake up puffy and bloated from the gluten and sugar. Even then a perfect lemon bar is usually worth it if I’m being honest.
I finally decided though that it was high time I came up with a legit keto lemon bar recipe that would meet my low carb and gluten free criteria (and save me from the morning after bloating.)
As an added bonus these keto lemon bars are relatively simple to make, and just as good or better than the “real” thing. I’m not just saying that either, I tested these out on crowds of non low carbers at several parties – all with rave reviews and no leftovers.
This keto lemon bar recipe is basically the love child of my Lemon Almond Shortbread Cookies (crust), and my Sugar Free Lemon Curd (filling) recipes, with a few minor tweaks.
I like my keto lemon bars a little on the tart side, but you can increase the sugar free sweetener in the lemon curd if you prefer them sweeter – or you can add more powdered sugar free sweetener to the top of them after baking.
I’m confident that you guys are going to love these low carb lemon bars – they simply scream “IT’S SPRING BABY!” and they’ll make you believe it – no matter what time of year it is where you are.
These low carb lemon bars use a homemade lemon curd filling for a brighter, more authentic flavor than shortcut versions.
Recipe Notes:
- When zesting your lemons, make sure you don’t zest any of the white coating. That’s the pith and it’s super bitter – you just want the bright yellow rind, which is where the oils and therefore flavor are. The best tool for zesting a lemon is a microplane grater in my opinion, but a box grater on the side with the small holes in it can work too if that’s all you have.
- Use FRESH LEMON JUICE in these keto lemon bars. That bottled stuff just won’t taste the same. Since you need lemon zest anyway, you might as well take a few seconds to juice the lemons you’re zesting for a superior lemon flavor. A handheld lemon crushy thing like this one is what I use and it’s super easy.
- You will need 5 – 6 average sized lemons to make these keto lemon bars.
- When cooking the lemon curd for these keto lemon bars, DO NOT LEAVE THE POT UNATTENDED. Whisk gently but constantly until the mixture thickens enough to coat the back of a spoon, and it has lightened slightly in color. This may take 10 – 12 minutes, and it will feel like it’s never going to happen and then WHAM it’s there and it seems to be instantaneous. Be patient – I promise it’s worth it!
- Some people choose not to strain the curd after cooking, and leave the bits of grated lemon zest in the bars. It’s strictly a matter of personal preference and if you don’t mind the texture of the zest in there, it won’t hurt anything to skip that straining step.
As always I can’t wait to hear what you think! Make these keto lemon bars ASAP and report back STAT! Bonus points if you snap a pic and tag @ibreatheimhungry on IG!
(fyi said bonus points are completely useless, much like my passport in 2020.)
Print
Keto Lemon Bars
- Total Time: 40 minutes
- Yield: 16 bars 1x
- Diet: Diabetic
Description
An easy and tasty Keto lemon bar recipe that’s just as good or better than the classic – but low carb and gluten free!
Ingredients
For the Crust:
- 6 tablespoons butter
- 2 cups superfine blanched almond flour
- 1/3 cup granulated sugar substitute (I used Swerve)
- 1 tablespoon freshly grated lemon zest
For the Filling:
- 1/2 cup butter
- 1/2 cup granulated sugar substitute (I used Swerve)
- 1/2 cup fresh lemon juice (from 5 – 6 lemons)
- 1/4 cup grated lemon zest
- 6 egg yolks
- 1/2 teaspoon xanthan gum
- 2 tablespoons unflavored collagen powder (or 1 teaspoon unflavored gelatin)
Instructions
For the crust:
- Preheat the oven to 350 degrees.
- Melt the butter in the microwave or a small saucepan.
- Add the almond flour, sweetener, and lemon zest, stirring until fully combined.
- Press the dough evenly along the bottom and 1/2 inch up the sides of an 8 x 8 inch square pan. For best results line the pan with parchment paper or foil first, then you can simply lift out the completed lemon bars.
- Bake for 10 minutes.
- Remove and cool while you make the filling.
For the filling:
- Melt the butter in a small saucepan on low heat.
- Remove from heat and whisk in sweetener, lemon juice, and lemon zest until dissolved.
- Whisk in the egg yolks and return to the stove over low heat.
- Whisk continually until the curd starts to thicken.
- Remove from the heat and strain into a small bowl.
- Whisk in the the xanthan gum and collagen or gelatin until dissolved and smooth.
- Pour the filling over the pre-baked crust and spread out evenly to the edges of the pan.
- Bake the bars at 350 degrees (F) for 15 minutes.
- Remove and cool.
- Sprinkle with Powdered Swerve before serving if desired.
- Cut into sixteen 2 x 2 squares.
Notes
To see a list of my favorite low carb products and brands that I recommend for sweeteners, flours, etc. you can check out the IBIH Pantry Ingredients Page!
- Prep Time: 10 minutes
- Cook Time: 30
- Category: Keto desserts
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 2 x 2 square
- Calories: 193
- Fat: 19g
- Carbohydrates: 2g net
- Protein: 4g
More Keto Lemon Recipes You’ll Love
Keto Lemon Dressing aka. Vinaigrette
Keto Lemon Magic Custard Cake – Low Carb
Easy Keto Lemon Cheesecake – Low Carb
Keto Lemon Muffins – Low Carb and Gluten-free
58 best low carb lemon dessert recipes
Paula says
I am getting ready to try the lemon bars but I don’t have almond flour, ran out. :( Is it possible to use coconut flour in these? Thanks
Mellissa Sevigny says
I think the almond flour gives them the shortbread texture, straight coconut flour may not work as well.
Jenny says
I’ve made these before with swerve but am interested in using monkfruit instead. Do you know if it would affect the texture at all?
Mellissa Sevigny says
If anything I think monkfruit would be an improvement!
Eleni says
Hi, Mellissa,
I stumbled upon your site looking for lower carb lemon bars; the name of your site made me laugh out loud because it’s so true. I’m going to make these as soon as I have the ingredients.
I have 2 shallow questions, you may not want to answer. Your eye color is positively mesmerizing! Are you wearing contacts?? (not hitting on you – I’m an old, straight lady). Next, may I ask your lipstick color? It reminds me of a Clinique shade I used to wear all the time and can no longer find. I forgot to say I am also gray-haired and hoping that beautiful color might liven up my faded face. The aqua/rose combination is gorgeous on you! Forgive my curiosity, please. Thanks! Eleni
Mellissa Sevigny says
Thanks Eleni, I’m flattered! My eyes are really that color, thanks to my mom. The lip color I believe was a MAC shade, but I don’t have it anymore and I’m not sure what it was called – sorry! Hope you like the lemon bars!
Eleni Poulos says
Melissa,
How wonderful for both of you! Love the lemon bars, and thank you for sharing,
Eleni
Treva Burger says
The recipe worked great and they looked perfect, but i think they needed salt. I would have used salted butter, but I didn’t have any. I will next time. I appreciate the clear thorough instructions.
Argia says
Hi, I am a huge fan, and I am getting ready to make these bars tomorrow for my son’s birthday. I searched through the comments and your baking notes, but can’t seem to find if you use salted or unsalted butter for the crust. Thank you for all your amazing recipes.
Lindsay Milligan says
These are the best keto dessert I’ve found yet! So amazing!
Mellissa Sevigny says
Thanks Lindsay!
Honey says
This recipe is amazing. I love lemon, love lemon curd, love lemon bars but usually they’re too sweet and I can’t eat them. These I could eat the whole tray in a sitting. I did alter the recipe just a tiny bit just because I like the thought of having brown butter crust and I saw it on another recipe. I’m very happy I did that. So I browned my butter instead of just melting it and then I also made half of your recipe for the crust. I’m not a big crust fan. I just want a little bit of crust and a lot of filling so I cut your crust recipe in half but I thought this was amazing. I knew I should have strained my filling after I put the gelatin in but I didn’t so I ended up with a few little clumps of gelatin here and there but it still didn’t deter me I’ll just do that step next time.
Pamela says
Ohmygoodness! These are wonderful! We are actually eating these for breakfast! And, here’s the thing…I made these for my marvelous husband because I don’t even like lemon that much, but I love these!
Mellissa Sevigny says
Too bad for your hubby, now he has to share! 😂 Thanks for taking the time to let me know you’re enjoying them!
Sherri says
Hi there! Thanks for the recipe! I don’t have experience with custatds and I wasnt sure what I was looking for. I had to pause things for a few minutes between putting the yolks in and putting it on the stove. After about 6 minutes, it did thocken suddenly, but it was pretty lumpy so I wasn’t sure if it had cooked for long enough. It got thin again, so I just kept cooking until 12 minutes were up. It never really thickened back up. I strained it and put it in the oven with fingers crossed. I was wondering if you have suggestions for what to do if/when your custard thins again after thickening?
Camden says
Just like the classic recipe and super easy. Great for using up extra egg yolks.
Augustin says
I love it when I find keto recipes that are practically indistinguishable from the non-keto version. These lemon bars are perfect in that way. I also love this particular lemon curd recipe and use it even in recipes from other sites.