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.)
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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
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TristaTwelve says
Wonderfully tasty! I think, though, next time I will leave out the xanthan gum and just use the 1 tsp. of Great Lakes gelatin. I was wanting the lemon curd to be looser.
Kaitlyn says
I tried out this recipe and it was a huge hit! Everyone loved them and the tray was empty in a matter of hours. I added some nutmeg and vanilla to the crust as well as a little vanilla to the curd. I did also end up using a little more swerve to sweeten the curd as it was a bit more sour than I like. Otherwise i highly recommend this for pwople to try.
Tanya Stuart says
These bars are my absolute favorite. I make them for every holiday and they come out perfect every time.
Kate Breth says
I just made this for Easter and it was a hit!. I used powdered monkfruit instead of granular and added more sweetner so it wasn’t too tart. Just right for Easter & springtime.
Mellissa Sevigny says
Thanks Kate, so happy it was a hit!
Augustin says
These are my favorite keto lemon bars so far. I use allulose for the filling and swerve for the crust, and Garden of Life collagen, and they come out perfect every time.
Carrie says
I used monk fruit blend for the crust and fine allulose for the filling too. I didn’t use enough collagen, but still great texture.
Dee says
I had such a craving for lemon bars at work yesterday, so I was looking for a low-carb recipe and tried these last night. They are fantastic. Most lemon bars, lemon pies, etc., never actually have enough lemon in them for me. This one is awesome! I sifted the almond flour and sweetener, then I added a little unsweetened coconut for the crust. It came out so light and flaky that I think I’ll make that by itself as a cookie sometime! However, I zested 6 lemons and still didn’t get the full 1/4 cup of zest I needed for the filling, so I didn’t add any zest to the crust. I bet that would make it even better.
I used half monkfruit/half erythritol in both crust and filling. Because some people mentioned crystallization, I put the sweetener for the filling in a little coffee grinder and powdered them first. I hoped that might help them incorporate into the filling a little better. It seems to have worked, because there’s no crystallization. I also accidentally broke a yolk when trying to separate one of my eggs, so I threw the whole thing in there. With the xanthan gum and gelatin, it still set up just fine. I do notice a bit of that cooling sensation, which does hinder things a bit for me. I’m starting to bake more with allulose now that I can find it at my local stores. I will try that when I make these next time — and I will make these again!
Mellissa Sevigny says
Thanks for the detailed review and for leaving a rating Dee! I don’t love the cooling sensation from erythritol either so I’m looking for an alternative as well. I’m also going to try the allulose and then we’ll have to compare notes!
Karen says
I don’t like that cooling sensation either. I have learned to add INULIN powder when I use erythritol. I have figured out that about 1/3 the amount of of erythritol used, for the INULIN. That would be : 1/3 C of INULIN to 1C of erythritol. Give it a try! I know I a pretty happy with the results.
Mellissa Sevigny says
Thanks for the suggestion I will try it!
Deanna Knighten says
These were Amazing! Crust and filling – perfection!
I wondered if I could make a meringue with egg whites? But that would be double baking and I didn’t want to ruin my first batch!
Thank you for amazing recipes!
Mellissa Sevigny says
So glad you liked these Deanna – I too have wondered about a meringue layer but never got around to trying it! Let us know if you do and how they turn out if so!
Sandy says
These are AMAZING!!! I made them for Thanksgiving 2021 and they were such a hit I was asked to make them for Christmas this year. I also added a layer of cranberry puree that I made sugar free. Omg they are incredible. The lemon curd is perfection.
Carol says
I haven’t tried the recipe’ yet but wanted to respond that I see chefs on the food channels using a little kitchen torch to brown meringue all the time, then you wouldn’t need to double bake…
I look forward to trying this recipe’
Tori says
Recipe was great, the only problem I ran into was my crust didn’t seem to cook. It was still fairly mushy after taking it out of the over the second time with the curd. Any idea what could have gone wrong? Otherwise it was great! The curd tasted good and was the perfect consistency.
Griff Neilson says
Made this for my cheat meal and I am glad I did. I did not think it was too tart at all. I really appreciated that it was not overwhelming to my taste buds (tart or sweet) like other lemon bars I have tried. This was my experience. Thank you for the healthy alternative to this classic! :)
Eve says
Update made them again with the changes and froze a batch. They freeze great!
Mellissa Sevigny says
Thanks for letting us know Eve, I’ve never tried freezing them!